FEMAP Student Guide

SIEMENS

Femap 101 Student Guide Version 10.1.1 10 1 1

Siemens PLM Software

Proprietary and restricted rights notice

This software and related documentation are proprietary to Siemens Product Lifecycle Management Software Inc. © 2010 Siemens Product Lifecycle Management Software Inc. All Rights Reserved. All trademarks belong to their respective holders.

femap101-g-v10.1.1

Femap 101 Introduction to Femap with NX Nastran Student Guide

ii

Femap 101

Training Class Agenda Day 1 Topic

Lesson No

Workshop(s)

1

The FEA Modeling Process Using Femap



2

The Femap User Interface – Part 1



3

Geometry Creation and Editing



4

Materials and Properties



5

Boundary Conditions – Loads and Constraints



Day 2 Lesson No

Topic

Workshop(s)

6


7

Model Display and Visualization



8

Meshing



9

Analysis Set Manager

10

Postprocessing

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

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Day 3 Lesson No

Topic

Workshop(s)

11

The Meshing Toolbox



12

Midsurfacing



13

Assembly Modeling



14

Finite Element Modeling Debugging Student Topics

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L Lesson 1 The Th FEA M Modeling d li P Process

Using Femap Purpose This lesson provides an overview of general overview of Finite Element Modeling and Analysis and the tools in Femap available to generate FEA models. Topics •

What is Finite Element Analysis?

•

What comprises a FEA model?

•

Femap Modeling Process Flow

•

Femap Model Objects and Commands

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Fermp 101 Introduction to Femap with NX Nastran Student Guide

1-1

Lesson 1


What is Finite Element Analysis? A Finite Element Analysis (FEA) is a mathematical simulation of a physical structure when internal and external forces are applied to it. It can be used to simulate the following types of physical behavior: •

Structural

•

Thermal

•

Fluid Flow

•

Optical

•

Electromagnetic

Femap can be used to model the first four types of FEA models.

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Lesson 1


What comprises a FEA model? A Finite Element Analysis model is a collection of: •

Finite Elements - well-defined mathematical models of: •

Beams and Rods

•

S f Surface or Shell Sh ll elements l t

•

Solids (Tetrahedral or Hex)

•

Miscellaneous elements such as Springs, Mass, Rigid, and Contact

•

Material attributes

•

Boundary conditions (loads and constraints)

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Lesson 1


Takeaway A FEA model is at best, an approximation of a physical structure. The accuracy of the results from a FEA model are only as good as the quality of the mesh and the accurate application of material attributes and boundary conditions diti to t a model. d l

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Lesson 1


Femap Objects and Workflow for Generating a FEA Model

Geometry

Materials

Boundary Conditions • Constraints • Loads

Properties

Mesh

Analyze

Postprocess

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Lesson 1


Geometry Import Geometry File, Import Geometryy File, References

Create Geometry

Modify Geometry

Geometry commands Geometry,

Geometry, y commands Modify, commands

Direct CAD geometry interfaces  Solid Edge, NX (Unigraphics and Ideas) ProE, deas), ProE CATIA, CATIA and SolidWorks. Industry standard CAD geometry Interfaces 

Parasolid, ACIS, IGES, STEP, STL

Femap geometry creation and editing  Points, 2D and 3D curves  Surfaces  Solid creation and editing operations 

Midplane surface extraction and editing

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Lesson 1


Materials and Properties Materials Model, Material commands

Properties Model, Property commands

•

Isotropic

• Line elements

•

2D and 3D Orthotropic

• Plane elements

•

2D and 3D Anisotropic

• Volume elements

•

Elastomers – Hyperelastic, Foam, etc.

• “Other” elements

•

Analysis program specific types (NX Nastran, MSC Nastran, LSDyna, Abaqus, Marc)

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Lesson 1


Boundary Conditions Constraints Model, Constraint commands

Loads Model, Load commands

Femap models can contain multiple Constraint Sets and Load Sets Constraints and Loads can be assigned to geometry or meshes For loads, the Model Info window allows: 

Creation, editing, highlighting, and deletion of Load and Constraint sets.



Creation, editing, highlighting, and deletion of individual Loads, Load Definitions, Constraints, and Constraint Definitions.



Creation and editing of Body, Nonlinear, Dynamic, and Heat Transfer loads and settings.

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Lesson 1


Femap Model Objects and Commands – Meshing Mesh Control and Multielement Meshing Mesh, Mesh Control, commands Mesh, Geometry commands

Single Nodes

Model, Node… command

Single Elements

Model, Element… command

Additional mesh creation and editing tools are available through the Meshing Toolbox

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Lesson 1


Femap Model Objects and Commands - Analysis

Analyze

Model, Analysis command

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View Results (Postprocess) View, Select… (F5) View, Options… (F6) View, Advanced Post… commands

Report List, Output, commands Data Table operations


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Lesson 2

The FEMAP User Th U Interface I t f – Part 1

Purpose This lesson provides an overview of the Femap User Interface. Topics •

Femap Main Window Layout

•

Graphics Windows

•

Femap Main Menus

•

Toolbars and Customizable Menus

•

View Manipulation – Part 1

•

Dockable Panes

•

Model Info Tree

•

Entity Editor

•

Status Bar and Tray

•

Right Mouse Button

•

E tit Selection Entity S l ti

•

Setting the Pick or “Snap” Mode

•

Locate and Vector Dialog Boxes

•

Shortcut Keys

•

Online Help

•

Units

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Lesson 2


Femap Main Window Layout Femap Main Menu

Femap Title Bar

Femap Graphics Window Named Tabs for Graphics Windows

Tabs for “Stacked” Stacked dockable panes

Floating dockable pane

Current Model Status (FEMAP Menu Help when in command)

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FEMAP Status and Tray bar

FEMAP Trays


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Lesson 2


Graphics Windows Femap’s graphics windows have the ability to display: •

Wireframe, hidden line, or rendered FEA models

•

XY plots of functions and analysis results.

Multiple Models can be opened at the same time each with multiple views. •

A single model with multiple views has the view name displayed in the view tab

•

When multiple models are open, each view has their view tab displayed as Model Name : View Name

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Lesson 2


Graphics Windows (continued) Dynamic Viewing •

Views can be dynamically rotated, zoomed, and panned using the mouse.

•

Through the use of a supported SpaceBall device

True Windows - provide easy transfer from Femap to other Windows programs. •

Cut and Paste

•

Windows Metafiles

•

JPEG, BITMAP, GIF, TIFF, and PNG picture file formats

•

AVI and Animated GIF animation files

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Lesson 2


Femap Main Menus Provides access to most Femap operations through drop-down menus. •

Menu commands displays short-cut keys (hotkeys) and shows toolbar icons on menu (includes user-defined shortcut keys and icons, when assigned)

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Lesson 2


Customize Dialog Box Toolbars •

Turns toolbars on and off

•

Create and delete userdefined toolbars. toolbars

Commands •

Add regular and userdefined commands to an existing menu or toolbar.

K b Keyboard d •

Designate and manage shortcut keys (hotkey) combinations for specific commands.

User Commands •

Create and manage userdefined commands.

Options •

Set options on the toolbars such as using large icons, showing tooltips (with or without shortcut keys), and menu animation options (options are selected for ALL toolbars).

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Lesson 2


Toolbars Dockable Toolbars • Toolbars can be docked anywhere around the perimeter of p window. the main Femap • When “docked”, toolbars can be placed next to one another or “stacked” on top of one another.

Floating Toolbars •

Toolbars can be “peeled” peeled off the perimeter of the main Femap window and made to “float” anywhere within the main Femap window.

•

“Floating” toolbars can be reshaped.

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Lesson 2


Customizing Toolbars Three (3) methods to customize or create a new toolbar: •

Select the Tools, Toolbars, Customize command

•

Right-click in a toolbar pane or outside of any Femap pane

•

Click Cli k th the Customize C t i icon i (d (down-arrow icon) i ) on a d docked k d or fl floating ti ttoolbar lb and d th then select Customize from the context-sensitive menu.

Clicking the Down icon in a toolbar allows direct access to that toolbar and has options to disable commands in that toolbar.

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Lesson 2


Creating Custom Toolbars Click the New button inside the Toolbars tab, then give the new toolbar a unique name. 1. Click the Commands tab and choose a category. 2. “Drag” the desired command or menu onto the blank toolbar 3 Alter 3. Alt any icons i using i the th individual i di id l icon i editing diti ttools l explained l i d on th the previous i page 4. Close the Customize dialog box and start using the new user toolbar.

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Lesson 2


Toolbars – Icon Editing Menu While the Customize Dialog box is open, you can also edit individual icons by placing the cursor over any icon and clicking the right mouse button. This will bring up a menu as follows:

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Lesson 2


View Manipulation View Rotation, Zooming and Panning View Orientation Toolbar Entity Display Toolbar View Toolbar

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Lesson 2


View Rotation, Zooming and Panning Views can be dynamically manipulated with the mouse by holding a mouse button and keys and dragging the mouse in the Graphics window:

Action

No command active

While a command is active

Rotate

Left or Middle mouse button

Middle mouse button

Pan

Ctrl+Left or Ctrl+Middle mouse button

Ctrl+Middle mouse button

Zoom

Shift+Left or Shift+Middle mouse button

Shift+Middle mouse button

The mouse’s Scroll wheel can be used for dynamic zooming. Femap Preferences can be modified to swap the use of the Ctrl and Shift keys for dynamic viewing viewing. •

Located under the User Interface tab, Mouse Interface options.

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Lesson 2


View Orientation Toolbar The View Orientation toolbar allows you to rapidly reorient a view to one of Femap’s standard nine (9) views. •

This toolbar is not activated as part of the standard Femap GUI layout, you will need place it. to activate and p

The Isometric, Dimetric, and Trimetric view orientation(s) can be modified using Femap’s Femap s Preferences. •

Select the View tab and set the angles for these views under the View and Dynamic Rotation section.

As an alternative, you can use the View, Rotate, Model command (F8 hotkey) to rotate or orient views. •

Version 10 added the option to “Rotate Around” any coordinate system, including those defined by the user.

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Lesson 2


Entity Display Toolbar The Entity Display toolbar toggles the display of different entity types within a Graphics window.

Coordinate Systems

Constraints

Text

Nodes

Surfaces

Regions

View Analysis

Elements

Model Toggle Loads

View Geometry Toggle

Curves

Connectors

View Labels

Toggle Points

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Lesson 2


Entity y Display p y Control with the View Visibility dialog box The View Visibility dialog box controls the display of entities in a manner similar to the Entity Display toolbar, but in more detail. •

Access via the View, Visibility command, the Ctrl+Q hotkey or by clicking the View Visibilityy icon on the View toolbar.

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Lesson 2


View Toolbar The View toolbar allows control of the active view orientation, magnification, view style, and layers.

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Lesson 2


View Toolbar – View Style Icon Pulldown Menu The View Style menu controls settings for view type (wireframe, hidden line, etc.), mesh display, element colors, mesh size indicators and other commonly used display settings.

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Lesson 2


Dockable Panes There are seven (7) standard dockable panes • Model Info • Meshing Toolbox • Entity Editor • Entity Info • Data Table • Data Surface Editor • Messages Window

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Two other dockable panes are available for customization of Femap: • Program P Fil File • API Programming Can be turned on and off using the Tools menu and the Panes toolbar. Panes can be resized when docked or floating.


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Lesson 2


Dockable Panes – Display Configurations Panes can be shown on the screen in a few different configurations •

Floating

•

Docked

•

D k d and Docked d “Stacked” “St k d” ((click li k T Tab b tto activate ti t P Pane))

•

Docked and Tabbed (Retracted) – Place cursor over tab to have pane “fly-out” and be used (Docked and Tabbed Panes can also be “Stacked”)

The Push Pin Icon is used to toggle a dockable pane from simply “Docked” to “Docked and Tabbed”.

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Lesson 2


Dockable Panes - Positioning Docking position indicators are used to position Dockable Panes in specific places in the interface and can also be used to “stack” the panes. •

Docking locations appear as arrows.

Docking position indicators only appear when a dockable pane is being dragged from one position to another. •

An outline of where the pane will be positioned will appear when the cursor is placed over a specific Indicator.

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Lesson 2


Messages Window Can be turned on and off using the Tools, Other Windows, Messages menu •

Provides information on commands Femap is performing, and their status.

•

List and error information

U d k window Undock i d b by d double-clicking bl li ki on the th Title Titl Bar, B return t to t previous i docked d k d size i b by double-clicking Title Bar again. •

Messages window can be resized when docked or floating.

Copy or Save Information from List •

Highlight and Cut

•

S Save tto File Fil

Note:

When typing in the Messages window, anytime you type a shortcut key, the command assigned to the key will be invoked.

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Lesson 2


Messages Window – Other Options Format contents of the Messages window with the context sensitive pop-up menu (rightmouse click).

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Lesson 2


Model Info Tree Can be turned on and off using the Tools, Model Info command or with the Panes toolbar. Provides quick access to “top-level” entities in Femap through an easy to navigate tree structure. t t Top-level items found in the tree include: •

Coordinate Systems

•

Geometry – Solids and Sheet Solids Only

•

Connections

•

•

Properties

•

Regions

•

Connectors

Model •

Elements

•

Materials

•

Properties

•

Layups

•

Loads and Constraints

•

Functions

•

Data Surfaces

•

Analyses – Analysis Sets

•

Results – Output Sets

•

Views

•

Groups

•

Layers

•

Selection List

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Lesson 2


Model Info Tree – Addition Features and Selection List Context-Sensitive menus available for each item in the Model Tree by highlighting an item then clicking the right mouse button. Multiple entities can be highlighted at the same time in order to perform operations on all off the th entities titi att once. Active Entity of each entity type is displayed with Blue text in the tree. Selection List – used when Select Multiple is active in the Select Toolbar. •

Lists each entity type currently in the selection set

•

Displays the number of entities of each entity type in parentheses

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Lesson 2


Model Info Tree – Icons •

Collapse/Expand All •

•

Collapses or expands ALL categories in the Model Info tree at once. Can be used to only show what you need to view specific entities. Reload From Model

• •

Reloads the Model Info tree with all current information from the model. Always collapses the whole tree completely. Reset All Visibility Options

• •

Toggles the display of all entities on Send To Data Table

•

Sends selected data to the Data Table pane for sorting, filtering, and evaluation. Data Table MUST be open and unlocked for this icon to be used.

Show When Selected pull down 

Note:

Toggle on/off and settings for highlighting of selected objects. Similar to the Window, Show Entities command.

Defaults for Show When Selected can be set in the Show Entities Defaults section found on the User Interface tab of the Preferences dialog box.

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Lesson 2


Model Info Tree – Context Sensitive Menus Context-Sensitive menus are available for each item in the Model Tree by highlighting an item then clicking the right mouse button. Menu is different for each entity type in the tree. Some context sensitive menu commands require that multiple entities be chosen to activate a command. (e.g., MultiSet Animate) •

Select individual entities while holding down the CTRL key.

•

Hold down the SHIFT key and select a first entity and a last entity to select a continuous list of entities.

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Lesson 2


Entity Editor Turn on and off with the Tools, Entity Editor menu or with the Panes toolbar. Provides information of specific entities in Femap displayed using different types of fields. The types of fields include: •

Numeric Value - Enables you to enter a numeric value for a specific field

•

Text - Text can be typed directly into these fields. Usually in a Title, Text, or Notes field

•

Drop-down menu button - Button has arrow facing down. Lists options for that can be selected for a particular field.

•

Options button - Button has three dots. Brings up the color palette or a dialog box that is used to change the information in that specific field.

•

Read Only - Cannot be changed. Shown in Blue text.

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Lesson 2


Entity Editor (continued) Entities can be sent to the Entity Editor using the following entry methods: •

Model Info pane •

•

Select Toolbar •

•

When an entity in the tree is highlighted, it will appear in the Entity Editor (Analyses and entities in the Selection List from the tree will not populate the Entity Editor when highlighted) When activated, the last chosen entity will appear in the Entity Editor pane.

D t Table Data T bl pane •

Once the Data Table has entity data in it, every time a row containing entity data in the table is highlighted, it will appear in the Entity Editor.

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Lesson 2


Entity Editor – Icons

•

Lock/Unlock Toggle - When unlocked, the Entity Editor will always display the entity that was last selected using an entity entry method. When locked, the data in the Entity Editor will remain there until the pane is unlocked.

•

Copy to Clipboard - Copies the current data in the Entity Editor to the clipboard so it can be pasted into the Messages window or an outside program

•

Clear All – clears the contents of Entity Editor window window. Does not delete the entity.

•

Categorized - Default listing method of the Entity Editor. For each entity, groups similar parameters, options, and settings together for more efficient use.

•

Alphabetic - Displays all the fields without any categories in alphabetical order

•

Collapse/Expand All - Collapses or expands ALL categories in the Entity Editor at once. Can be used to only show what you need to modify specific entities.

•

Reload From Model - Reloads the Entity Editor fields with the values that are currently in the model for the chosen entity. Use this to recover the original values for all the fields, except for modifications made with a prior Update Model action.

•

Update Model - Applies any changes made in the Entity Editor to a chosen entity and saves the changes to the model database

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Lesson 2


Entity Editor – Other Options Expand/Collapse toggles •

Allow you to collapse and expand individual categories and sub-categories inside the Entity Editor.

Entity Editor Help •

Shows a title and short description of what each field of every entity represents. Also documents the Nastran Bulk Data entry (if applicable) the field will produce when a Nastran Input File (*.DAT, *.BDF, or *.NAS file usually) is exported.

Context Sensitive Menus •

Different menus appear when the right mouse button is clicked depending on what type of field is currently highlighted. For instance, when a Text or Numerical Value field is highlighted, a menu will pop-up which hi h will ill allow ll you tto Undo U d (reverts ( t to t last l t saved value while field is still highlighted), Cut, Copy, Paste, Delete, or Select All.

Note:

You can use calculator functions (addition, subtraction, multiplication, and division), as well as exponentials (i.e. 1.234E4 for 12,340 OR 5.67E-3 for 0.00567) in any real number field.

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Lesson 2


Status Bar and Tray Can be turned on and off using the Tools, Other Windows, Status Bar command. •

Located at bottom of Femap Main Window

•

Provides running total of nodes and elements in model.

•

Displays a short description of commands when in the menu structure of Femap or positioned over icon.

Tray on Right •

Provides Access to Current Entities

•

Displays Active Property, Load Set, Constraint Set, Group, and Output Set

•

Change Current Entity or create a new one

•

Right-clicking the Status Bar brings up a customization menu which can be used to toggle individual Tray items on and off

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Lesson 2


Right Mouse Button Provides quick and convenient access to common commands. OK and Cancel for commands and dialog boxes Previous Command •

Recalls the last command executed

Modify the Workplane. Show Tooltips •

When activated, shows information for a highlighted entity in a “Tooltips” window (small yellow window in the main graphics window)

•

Works much like Dynamic Query in previous versions of FEMAP when there is entity active in the Select toolbar

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Lesson 2


Right Mouse Button - continued Picking Options - Snap To, Pick Query, Pick Any Inside, Pick All Inside •

See section on setting the “snap” mode”

Select •

This menu off options Thi ti allows ll you to t control t l which coordinates will be selected when ou use the graphics cursor to pick a location.

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Lesson 2


Right Mouse Button - continued Equations •

Brings up the Equation Editor in FEMAP (a field must be highlighted in a dialog p to be available). ) box for this option

Visibility, Post Data, and XY Data •

Convenient method of changing view parameters

•

Menu commands for these option several layers down, right mouse button provided easy access

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Lesson 2


Entity Selection Dialog Box The Entity Selection dialog box is used by commands to build a list of entity IDs that will be used for the operation. •

The Add method allows you to graphically, and through Methods, add entity IDs to the list of IDs.

•

The Remove method allows you to graphically remove entity IDs from the list, and is dependant on the order you removed the entities. So if you were to add the entity ID after removing, it would still be included in the list.

•

The Exclude method allows you to exclude entity IDs permanently from the list (Used primarily with Groups)

•

The Delete command will delete the entity ID from the list list.

•

Selection methods with the Method button vary depending on the entity type.

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Lesson 2


Entity Selection Dialog Box - Continued The Entity Selection dialog box is used by commands to build a list of entity IDs that will be used for the operation. The Pick button allows you to: •

Switch between Normal, Normal Front, Front and Query picking

•

Select entities graphically from the screen using a Box, Circle, Polygon, or Freehand shape •

Hotkeys are available for the following: •

Box – press and hold the Shift key

•

Circle – press and hold the Ctrl key

•

Polygon – press and hold the Ctrl+Shift keys

•

Select based on Coordinate(s), Around a Point, Around a Vector, or Around a Plane

•

Specify options for selecting Combined Curves and Boundary Surfaces

•

Add additional entities based on entities already selected using Add Connected Fillets and Add Tangent Surfaces

•

S l t entities Select titi matching t hi th the Color C l selected l t d ffrom a color l palette. l tt

•

Select From List button. For objects that have "Titles" the "Select from List" button can be used to choose entities from a list dialog box. Ctrl+L in a dialog box field brings up the list of "Titled" entities.

•

The Preview button graphically highlights the entities selected.

Note: Clicking the icon in a Femap Entity Selection dialog box takes you directly to the Femap User Guide through on-line help and has a table of all the Selection methods for each entity type.

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Lesson 2


Using g the Filter in the Select from List Dialog Box With Femap v10.1.1, when the Select from List dialog box is used, you can filter the selection list to reduce the number of entries to select from . •

Enter the filter string and push the Filter g those entries that contain the filter string

•

You can enter additional filter strings or push the Clear All Filters icon to clear your filter and return to the original, unfiltered selection list.

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icon to reduce the search list to the


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Lesson 2


Setting the Pick or “Snap” Mode For any Femap operation where a location is used to specify a coordinate, you can set the Pick or “Snap Mode” to one of four types: •

p to Screen ((default)) Snap

•

Snap to Grid – snaps to the nearest grid location on the current XY Workplane regardless whether the workplane’s display is toggled on or off.

•

Snap to Point – location snaps to the nearest p point on the visible model. Points do not need to be displayed.

•

Snap to Node – location snaps to the nearest node on the visible model. Nodes do not need to be displayed.

The snap mode can be specified by e either: t e •

Using the standard contextsensitive menu activated by clicking the right mouse button in the Graphics pane.

•

Using the Snap Mode pulldown menu on the Select p toolbar.

The current Snap Mode is always displayed on the Select toolbar.

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Lesson 2


Locate Dialog Box Whenever a location is required in Femap, the Locate – Enter … dialog box will appear. •

Enter coordinates directly (relative to specified Coordinate System) or

•

Click the Methods button to change the method of specifying a location

•

See section 4.3.1 Entity Selection in the Femap User Manual (user.pdf).

N t S Note: Setting tti the th Method M th d in i th the Locate L t dialog box does NOT change the Snap Mode

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Lesson 2


Vector Locate Dialog Box Whenever a vector is required in Femap, the Vector Locate – Select Vector … dialog box will appear. •


•

Click the Methods button to change the definition method of the vector vector.

Note: To change the Method of specifying the coordinates of the vector, place the cursor in one of the coordinate boxes, and press the Ctrl+Z hotkey.

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Lesson 2


Plane Locate Dialog Box Whenever a Plane is required in Femap, the Plane Locate – Specify Plane … dialog box will appear. •


•

Click the Methods button to change the definition method of a plane plane.

Note: To change the method of specifying the coordinates of the plane, place the cursor in one of the coordinate boxes boxes, and press the Ctrl+Z hotkey.

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Lesson 2


Shortcut Keys Femap contains preprogrammed shortcut keys for commonly used commands. •

F5 - View Select, F6 - View Options, F8 - View Rotate, Ctrl+D - View Redraw, Ctrl+A - View Autoscale Visible, Ctrl+G - View Regenerate, Ctrl+Z - Undo, and pp A of User Guide)) Manyy More. ((See Appendix

•

Preprogrammed Keys shown on Menu Structure.

Dialogue Box Keys – available when in a command. •

Ctrl+A - Measure an Angle

•

Ctrl+C - Windows Copy

•

Ctrl+D - Measure a Distance

•

Ctrl+Z - Use Standard Coordinate Selection Dialog Box to define location.

•

And Many More (See Appendix A of User Guide)

Customizable Shortcut Keys – Use the Tools, Toolbar, Customize command •

Customized shortcut keys can be saved to a .LAYOUT file and imported into other installations of FEMAP FEMAP.

•

In some cases, importing a .LAYOUT file with customized shortcut keys only into a new version of FEMAP will recreate some or all of the customized shortcut keys.

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Lesson 2


Creating Customized Shortcut Keys Click the customize triangle on any toolbar and select Customize from the menu, then choose the Keyboard tab. Choose a Category from the drop down list, then highlight the command from the C Commands d list.. li t Once the command is highlighted, place the cursor in the Press new shortcut key field and key in a new character or keyboard combination. If the key or keyboard combination has already been defined, FEMAP will bring up a dialog box stating “This shortcut is currently assigned. Do you want to re-assign this shortcut?” By clicking the Yes button, the key or keyboard combination will be added to the “Key assignments:” list and replace the previous command assigned to that key. After you have chosen the correct key or keyboard o eyboa d co combination, b at o , cclick c tthe e Assign button.

Note: When typing in the Messages window, anytime you type a shortcut key, the command assigned to the key will be invoked.

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Lesson 2


On-Line Help Menu Help - Femap provides description of each command while pointing at it or accessing it on the Status Bar . Help is context sensitive •

Access a command

•

Click F1 to access HELP

•

Shift + F1 to choose a command with the “What’s This?” cursor.

•

Help Window will appear with description of the current command.

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Lesson 2


FEMAP Help Menu Full On-Line Help System accessed through the Help Menu. •

Toolbars

•

Dockable Panes

•

NX Nastran – access the complete NX Nastran documentation set

•

What’s New

•

Examples

•

Using Help

•

Programming – access the API Programming Guide

•

Basic Language – access when the API Programming window is open

•

Tip of the Day

•

Femap on the Web

•

Technical Support – access FEMAP Technical Support via the web

•

About – access to licensing info and input of license keys

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Lesson 2


Femap Model Units Femap is unit less and does not track or maintain consistent units But… •

Femap standard material and beam section property libraries use in-lbs units

•

Solid geometry defaults to inches on desktop, meters in model file database •

Parasolid (regardless of product) always stores data in meters

Units conversion tool lets user convert units of data in model User must be aware of current units system being used •

You can use the File, Notes command to make a notation for future reference and to add a comment in the analysis file.

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Lesson 2


Units Conversion Use the Tools, Convert Units command to convert units. •

Convert all quantities using conversion of basic units

•

Convert specific entities with individual conversion factors

E.g. convert N-mm units in model to N-m •

Length: 0.001 m = 1 mm

•

Mass: 1000 kg = 1 tonne

•

Force: 1 N = 1 N

•

Energy: 0.001 N•m = 1 N•mm

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Lesson 3

G Geometry t Creation C ti and d Editing Editi

Purpose This lesson provides an overview of the Femap’s geometry import, creation and editing tools. Topics 

Geometry Overview



Parasolid Geometry Kernel



Geometry Import



Solids Overview



Geometry Cleanup



Wireframe Geometry Creation and Modification



Surface Geometry Creation and Editing



Solid Geometry and Editing



General Geometry Modification Tools



Additional Geometry Tools for Meshing

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Lesson 3


Geometry Overview Femap supports the creation and modification of wireframe, surface, and solid geometry using the Parasolid geometry kernel Femap reads multiple CAD formats Femap geometry creation and editing •

Points, 2D and 3D curves

•

Surfaces

•

Solid creation and editing operations •

•

Supports Solid, Sheet and Non-manifold Bodies

Midplane surface extraction and editing (to be covered in a separate lesson)

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Lesson 3


Parasolids Geometry Kernel Parasolid geometry is always stored in SI (meters) no matter what unit it is created in. •

Parasolid has a “box” with dimensions of 1000 x 1000 x 1000 with it’s origin at the center of the box

•

Default Coincident Point Tolerance of 1.0E-8

•

Parallel Tolerance of 1.0E-11 Radians

• Independent of product (Femap, UG NX, Solid Edge, etc.) From the Parasolid documentation: • “To allow precision to be handled correctly, all parts of a body must be within this b box…” ” •

“It is highly recommended to set the default unit in your application code to one meter…”

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Lesson 3


Solid Geometry Scale Factor Scaling of geometry is managed in Femap with the Solid Geometry Scale Factor. • •

Set in Femap’s preferences under the Geometry/Model tab e.g - When the models length is in millimeters, a length of 1.0 mm on the desktop will be stored as .001 001 meters in the database • Effectively scales the “box” to +/- 500,000 mm in X, Y, and Z from the origin.

Can also be set in the Solid Model Read Options dialog box for Parasolid and ACIS files and the STEP Read Options dialog box for STEP. •

When the dialog boxes are opened, the Geometry Scale Factor reflects Femap’s p preference. •

Geometry Scale Factor for Meters = 1

•

Geometry Scale Factor for Inches = 39.37

•

Geometry Scale Factor for Millimeters = 1000

Note:

If you change the Geometry Scale Factor to a value other than the value of Femap’s preference in one of these dialog boxes, this will update Femap’s preference to the value input.

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Lesson 3


Geometry Importing Import geometry with the File, Import, Geometry command. •

Import Geometry icon can be found on the Main toolbar

Direct CAD Interfaces •

Solid Edge (.par, .psm, .pwd, .asm)

•

NX Unigraphics (.prt)

•

NX I-deas (.idi)

•

Pro/Engineer (.prt, .asm)

•

C Catia v4 ((.mdl, .exp, .dlv))

•

Catia v5 (.catP*) – optional

•

SolidWorks (.sldprt, .sldasm)

Standard CAD Interfaces •

Parasolid

•

ACIS

•

STEP (AP 203 Solids, AP 214 Surfaces)

•

IGES

•

DXF

•

STL – reads .stl files as triangular surface mesh

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Lesson 3


Geometry Updates from CAD When solid geometry is imported from a CAD file, a reference to the source file of the geometry imported is created in the Femap model. •

The reference is based on the time/date stamp of the CAD file(s) imported, including ( ) to components p in an assembly. y modification(s)

The File, References command is used to view the status of a reference in Femap. •

If the time/date stamp is modified due to changes in the CAD model, this will be shown in the Reference Manager dialog box.

•

Femap’s default preferences are set to generate references upon import and to automatically check for reference updates when opening a model.

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Lesson 3


Solid Bodies A Solid body is completed enclosed by surfaces and has no gaps or dangling surfaces. •

Any Solid body is shown in the Model Info pane’s Geometry tree with this icon:

Note:

Running the Tools, Mass Properties, Solid Properties command will show that a Solid body has Volume.

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Lesson 3


Sheet Bodies Sheet bodies have one or more contiguous surfaces that do not enclose a volume. •

For multi-surface Sheet bodies, all surfaces must connect on a common edge with one other surface as with solid 2 below.

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Lesson 3


Non Manifold Bodies Non Manifold bodies are connected solids that can be a combination of Solid and/or Sheet bodies. •

Creating Non Manifold bodies from mid-surfaced geometry can also be very useful gp purposes, p , as surfaces coming g together g at “T-Junctions” share a for meshing common curve.

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Lesson 3


Geometry Checking and Cleanup After importing geometry, it is strongly recommended that you check and fix all solid geometry before attempting to mesh •

The Solid, Geometry, Cleanup command checks the validityy of selected solids in your Femap model file.

•

The Meshing Toolbox has the Entity Locator tool to locate curves and surfaces within solids by specifying a search method and size. This will be covered in detail in Lesson 11 – The Meshing Toolbox.

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Lesson 3


Geometry, Solid, Cleanup Command Remove Redundant Geometry •

Cleans curves imprinted on surfaces and merges surfaces that are part of y g original g surface. the underlying

Remove Sliver Surfaces •

Removes small “sliver” surfaces resulting from inaccuracies in solid geometry operations.

Check Geometry •

Checks the validity of the solid. Will show that an imported solid body is in reality a sheet solid if imperfections are detected.

Match Model Scale Factor •

Use when solids imported are at a different Solid Geometry Scale Factor than the factor set in Femap preferences.

•

Adjusts the selected solid(s) to the factor set in Femap preferences.

•

Must have Check Geometry option enabled.

Advanced cleanup options - See section 3.4.2.22 of the Femap Commands manual. •

Has options to repair and remove small features features.

•

Surface Heal and Stitch option is similar to Explode and Stitch commands. Can only be used on one solid at a time. Note:

If you still have problems cleaning geometry for meshing, an alternative technique is to Explode the problem solid, then Stitch it back together.

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Lesson 3


Wireframe Geometry Creation and Modification Topics Workplanes Wireframe Geometry Defaults Lines Arcs Circles Splines Wireframe Geometry Modification Boundary Surfaces

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Lesson 3


Workplanes The Workplane is used to define the local “X-Y” plane for 2D wireframe and some solid geometry creation commands. Access via the Tools, Workplane command or the F2 hotkey. •

Snap Options control display of the grid spacing, etc. of the workplane

•

Workplane display can be toggled on and off with the View Style, Workplane icon on the View toolbar

•

Grid display options in the View Options – Tools and View Style dialog box controls color and fill settings for the workplane

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Lesson 3


Wireframe Geometry Defaults Default colors for curves are set in Femap’s Preferences dialog box. •

Color can also be set for a model with the Tools, Parameters command or in the View Options dialog box.

Color, ID, Default Length, Spline Order, etc. are set in the Geometry Parameters dialog box. •

Press the Parameters button in the Locate - … dialog box to access the Geometry Parameters dialog box

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Lesson 3


Lines Creation with the Geometry, Curve – Line commands: •

•

Locate on the Workplane: •

Project Points

•

Horizontal

•

Vertical

•

Perpendicular

•

Parallel

•

Midline

•

At Angle

•

Angle to Curve

•

Point and Tangent

•

Tangent

•

Rectangle

Locate in 3D space: •

Continuous

•

Points

•

Coordinates

•

Offset

•

Vectored

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Lesson 3


Arcs Arcs are always placed on the Workplane Arc creation with the Geometry, Curve – Arc commands: •

Center-Start-End

•

Radius-Start-End – two points on the arc define the start and end of the arc. A positive radius will create an arc less then 180 degrees while a negative radius will generate an arc greater than 180 degrees.

•

Angle-Start-End– two points on the arc define the start and end of the arc; a positive angle will generate the arc from the start to the end in a counterclockwise direction – a negative angle will generate the arc clockwise from the start point to the end point..

•

Chord-Center-Start – locate the center, start point for the arc, and a chord length less than twice the radius.

•

Points – locate the start point, a point on the arc, and the end.

•

Center and Points – use this to create an arc in 3D space. Specify by four points: Center, start, end, and a fourth point that defines the direction of the arc.

•

Start-End-Direction – specify the start and end points, and the tangent direction for the start point.

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Lesson 3


Circles Circles are always placed on the Workplane Circle creation with the Geometry, Curve – Circle commands: •

Radius – two points define the center and a point on the circle.

•

Diameter – two points on the circle define the diameter.

•

Center C t – define d fi th the center t and d th the radius of the circle.

•

Two Points – locate two points on the circle and enter the radius.

•

Point-Tangent – locate the center point and a tangent curve.

•

Concentric – create a circle by selecting an existing circle and the new circle’s radius.

•

Points on Arc – create a circle by three points.

•

Center and Points – create a circle by defining the center, starting point on the circle, and a point defining the positive direction of the circle.

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Lesson 3


Splines Splines can be generated by Control Points or by Points on the spline (the spline’s control points are automatically generated by Femap). Four (4) point Bezier splines are created when using the following commands: •

Ellipse

•

P b l Parabola

•

Hyperbola

•

The Equation spline is created by specifying coefficients of parametric cubic equations.

•

A Tangent spline is created by specifying the start and end points of a spline and the tangents at those points.

•

The spline created by the Blend command creates a spline blending two curves. A Blend Factor controls the interior shape.

•

The Offset spline uses a point projected onto the Workplane to determine the offset location.

•

Combine a set of contiguous curves into a single curve using the Multiple Curves command. Not to be used with sharp corners.

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Lesson 3


Boundary Surfaces and Sketching The Geometry, Boundary Surface command creates planar surfaces made up of a boundary curves. This command is very useful when the wireframe geometry needs to be converted to surfaces and/or solids. •

p holes. Can include multiple

•

Boundary Surface(s) are non-Parasolid surface(s) – use the Geometry, Surface, Convert command to convert into a Parasolid surface.

The Geometry, Sketch command creates a Boundary Surface from curves created during the Sketch command sequence. •

Also accessible from the Solid toolbar – once the sketch is completed, you have the option to extrude or revolve the “sketched” boundary surface.

The Modify, Edit, Boundary command allows you to add or remove curves from an existing Boundary Surface.

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Lesson 3


Wireframe Geometry Editing Wireframe geometry can be edited with the following commands: •

Modify, Trim •

•

Modify, Extend •

•

Trims and/or extends the selected curves to their intersection point.

Modify, Fillet •

•

Splits the selected curve(s) at a point projected from the selected point normal to the curve.

Modify, Join •

•

Extend the end point of the selected curve(s) to a point projected from the point normal to the curve. curve

Modify, Break •

•

Trims the intersection curves curves. These curves must extend past one another – will not extend to the intersection.

Creates a tangent arc between the two selected curves.

Modify, y, Chamfer •

Note:

Creates a chamfer between the two selected curves.

Except for the Break operation, these commands cannot be applied to solid or surface geometry curves curves.

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Lesson 3


Surface Creation and Non-Manifold Geometry Commands Edge Curves •

Creates a surface from 3 or 4 curves.

Aligned Curves •

Lofts a surface through curves.

Sweep •

Used to sweep multiple-curve cross sections along a curve

Convert •

Used to convert boundary surfaces and surfaces made with the standard FEMAP geometry engine into Parasolid surfaces. Only planar boundary surfaces will be converted with the Convert command.

Remove Hole •

Used to remove interior voids in surfaces.

•

Can also be used to remove holes in solids.

N M if ld Add NonManifold •

Used to combine surfaces which do not enclose a volume and/or contain nonmanifold features (i.e., T-junctions) into a Parasolid “General Body”

•

May also be used to combine solids and surfaces into a Parasolid “General Body”

Recover Manifold Geometry •

Used to “break” break a Parasolid “General General Body” Body created using the NonManifold Add command into manifold sections.

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Lesson 3


Surface Curves The Geometry, Curve - From Surface set of commands are used to create curves on surfaces with the following techniques: •

Intersect – select two intersecting surfaces and/or solids.

•

Project – project the selected curve(s) normal to the selected surface(s) surface(s).

•

Project Along Vector - project the selected curve(s) along the specified vector onto the selected surface(s).

•

Parametric Curve – specify a location to generate a curve along a U or V direction on the selected surface.

•

Slice – split the selected surface(s) and/or solids by a plane.

•

Split at Locations – generate a parametric curve on a surface by specifying the start and end locations of the curve.

When the Update Surfaces option is enabled (default for new models), the curves become part of the surface and will “split” the surface into multiple surfaces (if the curves selected make up a closed loop). Otherwise, the curves generated by this p y internal curves of the surface. command are simply

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Lesson 3


Surface Curves (continued) The Offset Curve/Washer command generates curves offset from the selected curves. •

The Washer option is used to generate concentric arcs around the selected arc(s).

•

Offset Curves is used when the curves to be offset are around non-planar holes or around d non-circular i l iinterior t i ffeatures. t •

•

For cases where offsets of non-planar curves are requested, deselect the AutoSelect Surfaces option.

The Save Split Lines option creates connecting lines from the selected arc(s) to the concentric arcs and tags the surface around the arcs to use mapped four corner meshing.

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Lesson 3


Surface Curves (continued) The Pad command generates a square centered at the selected hole. •

Pad Width = 2 X Hole Diameter X Pad Size Factor Pad Size Factor = Pad Width / (2 * Hole Diameter)

•

Setup Mapped Meshing sets the mesh sizes around the four surfaces on the pad area for Four sided Mapped Meshing

•

Three (3) options for aligning the orientation of the pad: •

Auto Align

•

Vector Align

•

Tangent Align

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Lesson 3


Surface Curves Finally, three additional commands exist for creating curves on surfaces: •

Point to Point – select two points on a parametric curve is g generated. surface and a p Similar to the Split at Locations command, except that the points must exist on the surface. The surface is automatically selected by the first point.

•

Point to Edge – generates a curve on a surface by selecting a existing point on a surface and a curve on the interior or exterior boundary of the surface to project that point onto.

•

Edge to Edge - project the end points selected curve(s) along the specified vector onto the selected edge on the same surface.

Point to Edge curve

Edge to Edge curve

Point to Point curve

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Lesson 3


Solid Geometry Creation Extrude and Revolve 2D profiles Primitives •

Block

•

Cylinder

•

Cone

•

Sphere

Stitch Explode Editing operations •

Fillet

•

Chamfer

•

Shell

•

Thicken

•

Remove Face

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Lesson 3


Additional Solid Modeling Creation and Editing Tools Boolean operations •

Add

•

Remove

•

Common

•

Embed

•

Intersect

Face imprint and splitting •

Slice and Slice Match

•

Slice along Face

•

Embed Face

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Lesson 3


General Geometry Modification Tools Copy geometry via the following commands: •

Geometry, Copy

•

Geometry, Radial Copy

•

G Geometry, t Scale S l

•

Geometry, Rotate

•

Geometry, Reflect

Move geometry via the following commands: •

Modify, Project •

•

Projects points onto curves, surfaces, vectors and planes

Modify, Move To •

Moves a point from its current location to the selected location

•

Modify, Move By

•

Modify, Rotate To

•

Modify, f Rotate By

•

Modify, Align

•

Modify, Scale •

Allows scaling in three directions of the specified coordinate system

Modify a points location with the following command: •

Modify, Edit, Point

Change color and transparency with: •

Modify, Color

•

Modify, Transparency

Ch Change layer l with: ith •

Modify, Layer

Modify the ID of the geometry with: •

Modify, Renumber

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Lesson 3


Additional Geometry Tools for Meshing In some cases, you may need to modify geometry for meshing . In addition to the Geometry tools covered in this lesson, there are additional techniques that will be covered in subsequent sections: •

p Modeling g Midplane

•

Feature Suppression

•

Meshing Toolbox •

Entity Locator

•

Feature Suppression

•

Feature Removal

•

Combined / Composite Curves

•

Combined / Boundary Surfaces

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Lesson 4

M t i l and Materials dP Properties ti

Purpose This lesson provides an overview of creating and editing materials and properties with Femap. Topics •

Types of materials supported

•

Defining Materials

•

Other Types of Materials

•

Modifying Materials

•

Defining Properties

•

Beam Properties

•

Composite Laminates

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Lesson 4


Materials Supported by Femap Isotropic • Properties are constant in all directions (values entered as a single value). Orthotropic – 2D and 3D • Direction dependent. • Define in two planer or three principle directions. Anisotropic– 2D and 3D • Properties specified as a general 3x3 (2-D) or 6x6 (3-D) elasticity matrix. Hyperelastic yp • Materials subject to large deformations • Input distortional and volumetric deformations or stress/strain data. Other Types – material definitions unique to specific solvers • Nastran Fluid material (MAT10) • NX Nastran Hyperelastic Materials (MATHE, MATG) • MSC.Nastran Hyperelastic (MATHE) • LS-DYNA, MARC, and ABAQUS/Explicit. • User Defined material types for custom program interfaces.

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Lesson 4


“Other Types” of Materials “Other” Materials are for solver specific materials such as Nastran, NX Nastran, MSC.Nastran, LS-DYNA, MARC, and ABAQUS/Explicit Material types. The “other” material types specific to NX Nastran are shown in the Define Material dialog box below.

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Lesson 4


Defining Materials Create new materials with the Model, Material command or use the Model Info window (right-click on the Material object and select New). Default material type is Isotropic •

To select different material model, choose Type which appears on the top right of every material definition dialog box, and then select a different material type e type, e.g., g Hyperelastic. Hyperelastic

•

The default material type changes to the last selected type after changing the material type.



Type values directly into the fields provided; or



Access the material library by selecting the Load button

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Lesson 4


Defining Materials with Functions The Function Reference tab in the Define Material dialog box can be used to define Stress/Strain and Temperature dependent material values. •

Create new Functions without leaving the Define Material dialog box by clicking the fxy ((function)) icon button.

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Lesson 4


Modifying Materials Use the Modify, Edit Material command: •

Enter the Material ID you want to edit; or:

•

Select an element with the material you want to edit; or:

•

Alt Alternatively, ti l you can click li k th the Select S l t ffrom Li Listt icon; i or:

•

Use Method to select a material by Element, etc…

In the Model Info pane – right-click an individual material to be edited. •

Right-clicking on the Materials heading in the tree will select ALL materials for editing.

Note:

The Visibility Toggle icon to the left of the material name indicates whether or not objects using that material are displayed in displayed views of the Femap model.

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Lesson 4


Defining Properties A Property defines the element shape and associated material. Create new properties with the Model, Property command or in the Model Info pane, right-click on the Property object and select New. 

The default property (element type) is Plate.



Other types are selected with Elem/Property Type dialog box.



Selecting a different element/property type makes that type the default type.

Properties define additional analysis information for each element type, and are controlled by the element type.

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Lesson 4


Define Property Dialog Box Property data includes (depending on Element / Property Type) •

Material selection •

•

Select the Material icon ( ) to create a new material if the material for the new p property p y has not yyet been defined.

Property Values •

Thickness

•

Area, etc

•

Mass and inertia

•

Radius

•

Stress Recovery Points (Beams)

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Lesson 4


Bar and Beam Properties For Elem/Property Type Bar, Beam, or Curved Beam •

Enter values directly; or

•

Use the Shape button to enter cross-sectional data

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Lesson 4


Bar and Beam Shape Input Choose either a Standard or NASTRAN (PBEAML) category of Beam. Choose a standard shape from the Shape drop down list in the Cross Section Definition dialog box. •

Enter appropriate values for a shape and determine stress recovery points (Arrows can be used to dynamically position Stress Recovery and Reference points).

Choose General Section under Shape to select any planar surface as the cross section of a beam. Beam properties will be automatically calculated by after clicking OK.

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Lesson 4


Beam Orientation and Offsets Nodes on beams are located by default at the shear center of the beam. Offsets can be preset when creating or editing a Beam element. • Offset is from the shear center unless the option to Compute Shear Center Offset i tturned is d off. ff The Mesh, Mesh Control, Attributes on Curve command has options to preset beam Offset and Orientation.

Use the Modify, Update Elements, Line Element Orientation command to change orientation of the selected beam elements. The Modify, Update Elements, Line Element Offsets command is used to change the offset ff t off the th selected l t d beam b elements. l t • Can also change the offset by setting the location of the node to the beam Reference Point.

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Lesson 4


Beam Coordinate System Bar and Beam elements have a local coordinate system for each element. •

X axis of the beam is along the length of the beam •

Pt A is the start of the Beam

•

Pt B is i the th end d off the th B Beam

•

Y and Z axes are determined by the beam’s property definition.

•

FEMAP prompts |for an alignment vector when creating beam elements. l t

•

This vector is used to specify the direction of the Y-Axis specified in the Beam Property. Property

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Lesson 4


View Settings for Line and Planar Elements Femap’s View Options (View, Options or the F6 hotkey) has several settings to help in displaying line and planar element attributes. In addition, the View Style pulldown menu on the View toolbar has shortcuts to toggle li element line l t display di l settings tti on and d off. ff •

Offsets – toggle display of line (and planar) elements offsets.

•

Orientation – toggle display of line (and planar) element orientations.

•

Thickness/Cross Section – toggle display of line (and planar) element cross sections.

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Lesson 4


Modify, Update Elements Commands Reassign Element Properties and Materials Line Element settings Plane Element settings Element Order

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Lesson 4


Modify, Update Elements General Commands Type – assign a different property to the selected element(s). The element(s) must be of the same shape (Line, Plane, etc.) Formulation – modify formulation of elements of the same type. •

e.g. Change a Nastran Spring element to a Nastran CBUSH element.

Property ID – assign a different property ID to element(s) of the same type. Material ID – assign a different material to the selected physical property.

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4 - 15

Lesson 4


Modify, y, Update p Elements Commands for Line Elements Line Element Orientation – update beam/bar element orientations Line Element Offsets – update beam/bar element offsets Line Element Reverse Direction– Direction reverse element connectivity connectivity. ii.e.; e ; Swap A and B nodes. Beam/Bar Releases – update beam/bar element end releases Beam Warping – update beam warping as defined using NASTRAN SPOINTs Remove Cross Section – removes beam/bar element section shape while retaining properties

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4 - 16

Lesson 4


Modify, Update Elements Commands Modify for Plane Elements Reverse Normal/Orient First Edge – offers options for setting the normal direction and orientation of 2-D element(s). Material Angle – set or modify the material angle of selected element(s). Used for di ti d direction-dependent d t materials t i l and d llaminates. i t Split Quads – splits quad element(s) into triangles Adjust Plate Thickness/Offset – modify the thickness or offset of the selected element(s).

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4 - 17

Lesson 4


Modify, Update Elements, Adjust Plate Thickness/Offset Command Used to modify Element Offsets or Thicknesses of Plane Elements Modify the Offset distance of the selected plane elements. •

By default, nodes are located at the midplane (1/2 the thickness) of shell elements.

•

Use the Mesh, Mesh Control, Attributes on Surface command to preset the offset.

•

Constant element offset can also be set in FEMAP 10 and above when meshing surfaces by pressing “More Options” button and setting the appropriate options in the “Offset” section.

Change the Ch th Thickness Thi k off the th selected l t d elements, l t including i l di creating ti and/or d/ modifying dif i variable thickness shells •

Automatically creates new properties for the variable thickness planar elements.

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Lesson 4


Modify, Update Elements Miscellaneous Commands Linear/Parabolic Order – update the Order of the selected element(s) to/from Parabolic. •

To convert from Parabolic to Linear, select No in the first dialog box presented in the command.

•

You must manually delete and/or merge any midside nodes for elements converted from Parabolic to Linear.

Midside Nodes – moves the midside nodes on the selected element(s) to the midside of the element. Use after nodes have been moved. Rigid Thermal Expansion – assign a Coefficient of Thermal Expansion (α) to the selected Rigid Element(s). •

elements converted from Parabolic to Linear.

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Lesson 4


Composite Layups Layups are a Femap object that designates multiple composite plies •

Practical limit of 5000 plies per Layup

A Plyy has as the t e following o o g attributes: att butes •

Ply ID (number)

•

Material

•

Thickness

•

Angle

•

Global Ply ID – Used to designate a common ply ID for use in other layups. e.g. The OML or Outer Skin Ply for all layups.

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Lesson 4


Creating and Updating an Individual Ply New Ply - Once you have a Material, Thickness, and Angle specified, click this button to add the ply to the layup. Update buttons - Once a ply has been added to the list, the definition of that ply can be updated d t d using: i •

Update Global Ply

•

Update Material

•

Update Thickness

•

Update Angle

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Lesson 4


Duplicating and Modifying Ply Sequences Duplicate •

The selected ply or plies will be copied to the top of the Layup.

Delete •

Delete the selected ply or plies from the Layup.

Symmetric •

The “mirrored” plies will be added to the top of the Layup in reverse order of selection.

Reverse •

Reverse th R the order d off th the selected l t d plies li b based d on th the original i i l position iti (i (i.e., th the selected ply which was closest to the “Bottom of Layup” will now be closest to the “Top of Layup” in the list).

Move Up and Move Down •

The selected ply or plies will be moved closer to the “Top of Layup” (Move Up) or Bottom of Layup” Layup (Move Down) in the order selected. “Bottom

Rotate •

The selected ply or plies are rotated by the angle input in the Rotate Ply By dialog box. The order of the plies in the Layup is not effected.

Copy and Paste •

Copy and paste the selected ply or plies to the top of the current or another Layup.

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Lesson 4


Layup Editor – Layup Viewer The Layup Editor dialog box has the Layup Viewer icon that launches the Layup Viewer. Options to control display of: •

Thickness

•

Ply Angles

•

Titles

•

Color

•

Scale

The Copy icon pastes picture of the layup to Windows clipboard.

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Lesson 4


Composite Layup Mechanical Properties When the Entity Info window is active, the Laminate Equivalent Properties are automatically calculated and displayed when a Layup is created or edited. These properties are updated continuously along with modifications to the Layup. When the Entity Info window is not activated,, selecting g the Compute p button will display the calculated Laminate Equivalent Properties in the Messages window. These properties are NOT updated until the Compute button is reselected.

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Lesson 4


Composite Laminate Materials and Properties Composite Laminate Materials are generally designated as 2D Orthotropic materials. •

A Bond Shear Allowance should be specified for the Laminate element property. This value represents the bond strength between the bonded laminate sheets and is used to calculate a factor of safety against shear failure between laminate panels.

•

A Failure Theory must also be specified for the Laminate element property.

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Lesson 5


Purpose This lesson provides an overview of Femap’s capabilities in managing, creating and editing boundary conditions . Topics •

Constraint Sets and Constraints

•

Load Sets

•

Body Loads

•

Load Categories – Structural, Thermal, and Fluid loads

•

Creating and Editing Loads

•

Structural Load Types

•

Thermal Load Types

•

Fluid Load Types

•

Advanced Femap Loads

•

Load Set Options for Advanced Analyses

femap101-g-v10.1.1

Fermap 101 Introduction to Femap with NX Nastran Student Guide

5-1

Lesson 5


Constraint Sets The Model, Constraint, Create/Manage Set command creates a new Constraint Set or activates an existing Constraint Set. •

This command is also available in the Status Bar Tray and the Model Info tree.

•

You may create as many different Constraint Sets as necessary. necessary

•

Combine multiple Constraint Sets with the Model, Constraint, Combine command.

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Lesson 5


Constraint Set Manager Dialog Box Activating the Model, Constraint, Create/Manage Set command opens the Constraint Set Manager dialog box. •

The selected constraint set becomes the active set when the Done button is clicked.

With this dialog box, you can: •

Create a New Constraint Set.

•

Change the name of an existing constraint set by selecting a constraint set and then clicking the Update Title button.

•

Renumber the selected constraint set.

•

Delete (the selected) or Delete All constraint set(s). set(s)

•

Copy the selected constraint set.

•

Create Referenced Sets for Nastran SPCADD/MPCADD constraint sets. •

Requires that a combined set already be created and selected.

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Lesson 5


Creating New Constraint Sets Selecting the New Constraint Set button in the Constraint Set Manager dialog box activates the New Constraint Set dialog box. •

When a model has no constraint sets, you can only create a Standard constraint geometry y and nodal constraints. set. A Standard set is used to contain g

•

Clicking the More button will create the constraint set with the ID and Title and will then resets the options in the New Constraint Set dialog box to enable the creation of a new constraint set.

•

If one or more constraint sets are in a model model, you can also create a Nastran SPCADD/MPCADD Combination constraint set. •

A combined set references one or more Standard constraint sets.

•

When a Nastran deck is created by Femap, it writes out the Nastran SPCADD and MPCADD cards as needed.

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Lesson 5


Nastran SPCADD/MPCADD Combination Constraint Sets To reference Standard constraint sets, select a Nastran SPCADD/MPCADD Combination set the Constraint Set Manager dialog box, or right-click the constraint set in the Model Info pane and select and select Referenced Sets button in the dialog box or the context-sensitive context sensitive menu menu. The Reference Constraint Set for Nastran SPCADD/MPCADD dialog box will list the Available (standard) Sets and the Referenced Sets. Manage references by selecting one or more Standard reference sets and click the Add Referenced Sets or Remove Referenced Sets.

Note:

Nastran combined sets are not displayed in the graphics window unless the Show Constrained Entities is selected from the context-sensitive menu in the Model Info pane.

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Lesson 5


Creating Constraints Use the Model, Constraint commands, Constraint toolbar, or the Model Info tree.

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5-6

Lesson 5


Nodal Constraints Nodal Constraints - specify six (6) specific degrees of freedom with the Model, Constraint, Nodal command •

X translation = 1, X rotation = 4

•

Y translation = 2 2, Y rotation = 5

•

Z translation = 3, Z rotation = 6

•

Specify Coordinate System

Constraint Equations relate the motion or displacement of one node to the motion or displacement of one or more other nodes. •

Often referred to a MPCs

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5-7

Lesson 5


Geometry Constraints Geometric constraints - applied to geometry and “expanded” to nodes during export to an analysis file. •

Model, Constraint, On Point

•

Model Constraint, Model, Constraint On Curve

•

Model, Constraint, On Surface

•

“Expand” Geometric constraints manually by using the Model, Constraint, Expand command.

Available when constraining a surface.

Available for arcs or cylindrical surfaces. femap101-g-v10.1.1


5-8

Lesson 5


Editing Constraints Edit Constraints with: •

Modify, Edit, Constraint – Definition command

•

Modify, Edit Modify Edit, Constraint – Individual command

•

•

Individual constraints in a Constraint Definition may be edited. If the Constraint Definition is subsequently q y edited,, the individual edit is overwritten by the value of the Constraint Definition.

•

You can convert a Constraint Definition to Individual Constraints by right-clicking a Constraint Definition in the Model Info pane and selecting Remove Definition.

Model Info tree •

•

Includes the option to Edit Where Applied – add and/or remove entities where a constraint is applied. (new in v10.1)

Entity Editor

Note:

Constraints created prior to Femap v9.3 are shown in the Model Info tree as Other Constraints. This also applies to all FEMAP models created by importing analysis files.

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5-9

Lesson 5


Creating Load Sets The Model, Load, Create/Manage Set command creates a new Load Set or activates an existing Load Set. •

This command is also available in the Status Bar Tray and the Model Info tree.

•

You may create as many different load sets as necessary necessary.

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5 - 10

Lesson 5


Load Set Manager Dialog Box Activating the Model, Constraint, Create/Manage Set command opens the Load Set Manager dialog box. •

The selected constraint set becomes the active set when the Done button is clicked.

With this dialog box, you can: •

Create a New Load Set.

•

Change the name of an existing constraint set by selecting a constraint set and then clicking the Update Title button.

•

Renumber the selected constraint set.

•

Delete (the selected) or Delete All constraint set(s). set(s)

•

Copy the selected constraint set.

•

Create and manage Referenced Sets for Nastran Load Combination sets. •

Requires that a combined set already be created and selected.

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Lesson 5


Creating New Load Sets Selecting the New Load Set button in the Constraint Set Manager dialog box activates the New Load Set dialog box. •

When a model has no constraint sets, you can only create a Standard load set. A geometry, y, nodal,, elemental and bodyy loads. Standard set is used to contain g

•

Clicking the More button will create the load set with the ID and Title and will then resets the options in the New Load Set dialog box to enable the creation of a new constraint set.

•

If one or more load sets are in a model model, you can also create a Nastran Load Combination constraint set. •

A combined set references one or more Standard constraint sets.

•

When a Nastran deck is created by Femap, it writes out the Nastran LOAD cards as needed.

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Lesson 5


Nastran Load Combination Constraint Sets

To reference Standard constraint sets,, select a Nastran SPCADD/MPCADD Combination set, the Constraint Set Manager dialog box, or right-click the constraint set in the Model Info pane and select and select Referenced Sets button in the dialog box or the context sensitive menu context-sensitive menu.

The Reference Load Sets for Nastran SPCADD/MPCADD dialog box will list the Available ((standard)) Sets and the Referenced Sets. Manage references by selecting one or more Standard reference sets and click the Add Referenced Sets or Remove Referenced Sets. Set the Overall scale of the combined load set. Set the scale of the For Referenced Set. .

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Lesson 5


Standard Combined Load Sets You can also create a standard combined load set by combining multiple Load Sets into a new Load Set or another existing Load Set with the Model, Load, Combine command. •

Allows yyou to specify p y the Scale Factor of the Load Set(s) ( ) combined

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Lesson 5


Body Loads Body or Global Loads – applied to the entire model. •

Translational Acceleration (gravity) and Rotational Acceleration •

Use to apply the weight of the structure as a load

•

Rotational Velocity and Center of Rotations

•

Thermal – Default Temperature •

Required for all Nastran Heat Transfer analyses

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Lesson 5


Creating Load Definitions Use the Model, Load commands, Load toolbar, or the Model Info pane to create a Load Definition. •

A Load Definition is a container of all the loads created using one of the techniques above.

•

Load Definitions can be Removed which takes all the loads in the load definition and converts them to “Other Loads”.

Note:

Loads created prior to Femap v9.3 are shown in the Model Info tree as Other Loads. This also applies to all FEMAP models created by importing analysis files.

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Lesson 5


Create Loads Dialog Box After selecting the mesh or geometry to be loaded, the Create Loads on (Entity Type) dialog box is opened. In this dialog box, you specify: •

Title

•

Color and Layer

•

Coord Sys

•

Direction – this option is only available when specifying directional loads

•

Load Input Values

•

Phase - used for Frequency Response loading only

•

Midside Node Adjustment – follow the distribution of loads as specified in Femap’s Femap s preferences under the Geometry tab

•

Total Load – when multiple entities are selected to apply the load to, check this option to distribute the load across the selected entities so that the sum of the loads equals the load input value.

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Lesson 5


Editing Loads Edit Loads with: •

Modify, Edit, Load – Definition command

•

Modify, Edit, Load – Individual command

•

•

Individual loads in a Load Definition may be edited edited. If the Load Definition is subsequently edited, the individual edit is overwritten by the value of the Load Definition.

•

You can convert a Load Definition to Other Loads by right-clicking the Load Definition in the Model Info tree and selecting Remove Definition.

•

You can highlight any number of individual Loads of the same type found in the Other Loads section of a Load Set in the Model Info tree and combine them into a Load Definition using Create Definition

Model Info pane •

•

Includes the option to Edit Where Applied – add and/or remove entities where a load is applied. (new in v10.1)

Entity Editor

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Lesson 5


S Structural lL Load d types supported db by F Femap Load Type

Points

Curves

Surfaces

Nodes

Elements

Force











Force Per Length

-





-

-

Force Per Area

-

-



-

-

Force Per Node

-





-

-

B i Force Bearing F

-

-



-

-

Moment











Moment Per Length

-





-

-

Moment Per Area

-

-



-

-

Moment Per Node

-





-

-

Torque

-



-

-

Displacement









-

Enforced Rotation









-

Velocity









-

Rotational Velocity









-

Acceleration









-

Rotational Acceleration









-

Distributed Load

-

-

-

-



Pressure

-





-



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Lesson 5


Bearing Force on Surface Beginning with version 10.1.1 of Femap, you can apply a Bearing Force to a surface or surfaces eliminating the need to create Radial Coordinate System(s) and distribute the load using an Equation or Data Surface. •

p automatically y adjusts j the value of the individual nodal forces created when Femap the analysis deck is generated to equal the Magnitude input in the Create Loads on Surfaces dialog box

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Lesson 5


Bearing Force on Surface (continued)

•

The Load Angle (default = 180 degrees) is the total angle that the bearing load is applied across the selected surfaces. The direction of the bearing force is the bisector of the Load Angle

•

Uncheck the option for Normal To Surface to align the load with the vector used to define the direction of the bearing force

•

When multiple surfaces are selected, the Total Load option is automatically enabled spreading the specified Magnitude among all the surfaces selected selected, otherwise, the magnitude will be applied to each surface

•

When the Traction Load option is selected, the distributed load will “pull” on the surfaces pointing away from the solid volume instead of pushing on the surfaces pointing towards the solid volume

Once the inputs for the Bearing Loads are completed and the OK button is pushed, you will be prompted to specify the direction of the bearing force.

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Lesson 5


Bearing Force on Surface Example In this example, a 100 lb Bearing Force is applied to the each of the two holes on the vertical tabs on the bracket. •

Two different load sets are used – Load Set 1 uses the Normal Loads option and Load Set 2 p for Normal Loads disables the option

•

The upper bearing load in both load sets has the option for Traction Loads disabled while the lower load has the option enabled

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Lesson 5


Bearing Force on Surface Example (continued) Note the difference as to what nodes have loads applied around the two holes and the relative magnitude of the forces when Traction Loads are enabled or disabled once the loads are expanded.

Note the differences in the stress distribution and the elongation of the holes where traction is applied on the right vs. the hole on the left where traction is not applied.

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Lesson 5


Torque Loads on Surfaces Also beginning with version 10.1.1 of Femap, you can apply a Torque to a surface or surfaces eliminating the need to apply individual forces to surfaces or by assigning a moment to a node and connecting it to the surface nodes with a rigid element. •

p automatically y adjusts j the value of the individual nodal forces created when Femap the analysis deck is generated to equal the Magnitude input in the Create Loads on Surfaces dialog box

•

Once the inputs for the Torque are completed and the OK button is pushed, you will be prompted to the location and orientation of the axis about which the torque is applied.

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Lesson 5


Torque Example In this example, a 10 in-lb torque is being applied to the six grey surfaces below. The axis is being specified by using the Vector Global Axis method.

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Lesson 5


Torque Example - continued Once the load is applied, the torque load is displayed as a double-arrow vector representing the axis the torque is applied about with lines connecting the loaded surfaces to the torques moment axis.

When the Torque load is expanded, it appears as below.

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Lesson 5


Thermal Load types supported by Femap Load Type

Points

Curves

Surfaces

Nodes

Elements

Temperature











Element Temperature

-





-

-

Heat Flux (Heat Energy /Unit Area)











Heat Flux per Length

-





-

-

Heat Flux per Node

-





-

-

Heat Generation (Heat Energy / Unit Volume)











Element Heat Flux

-





-

-

Convection

-





-



Radiation

-





-



Element Heat Generation

-





-

-

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Lesson 5


Fluid Load types supported by Femap

Load Type

Points

Curves

Surfaces

Nodes

Elements

Static Fluid pressure









-

Total Fluid pressure









-

General Scalar









-

St Steam Q Quality lit









-

Relative Humidity









-

Fluid Height Condition









-

Unknown Condition









-

Slip Wall Condition









-

Fan Curve









-

Periodic Condition









-

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Lesson 5


Notes on Loads NX Nastran Displacement and Enforced Rotation loads require constraining the loaded object in the direction of the applied load •

e.g. A Displacement Load of x=.10, and y=.10 applied to a point requires that the corner be constrained in X and Y.

For NX Nastran Advanced Nonlinear (SOL601), loads should be applied with a timebased function. For solvers other than NX Nastran, refer to the Femap Users Guide for details on the loads supported by Femap for the solver used Also refer to that solver’s documentation on how to apply loads.

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Lesson 5


Advanced Femap Loads Femap has the ability to create variable loads via: •

Functions – time and frequency dependant loads

•

Variables – distributed or position dependent loads

•

D t S Data Surfaces f – advanced d d methods th d ffor creating ti variable i bl lloading di conditions diti

In Create Loads …dialog box:

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Lesson 5


Advanced Loading with Functions A Function allows you to create general X vs. Y tables of information. •

Only Time or Frequency dependant functions can be used to create loads.

•

Can also be used define nonlinear material properties.

Data can be created in four ways: •

By choosing a Single Value to enter in the X and Y values one at a time.

•

Using a Linear Ramp, you pick a starting and ending X and Y value.

•

An Equation where you specify the starting and ending values of X and delta X and then enter Y as a function of X X.

•

Use the Get function to attain data from a two column spreadsheet, or a listing of two comma separated values from a text file.

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Lesson 5


Advanced Loading with Variables You can make load equations as a function of a coordinate, nodal, or element centroidal location without having previously created a function. •

!x, !y, and !z return the X, Y, and Z coordinates of nodes, elements etc.

The Equation Editor is accessible with the CTRL+e hotkey. You can also combine Variable loads with Functions

Note:

Use the command Tools, Check, Sum Forces command to calculate sum off the th forces f and d moments applied.

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Lesson 5


Data Surfaces The Data Surface Editor pane allows more flexible and complex load definitions. After setup, the data surface can be edited directly using the Data Surface Editor. Access to all Data Surface types (except Tabular) available through the Create Load dialog boxes. allowing setup on the fly

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Lesson 5


One-dimensional Data Surfaces Along Coordinates Data Surface •

Interpolate linearly between at least three data points

•

Multiple piece-wise linear data points

•

Multiple splined data points

50 5.0

Enter or select the 3-D point locations and data values, and FEMAP does the rest

10 0 10.0 7.5

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Lesson 5


Two-dimensional Data Surfaces Between Coordinates Data Surface •

Bilinear interpolation between 2, 4, or 8 data points

•

Parametric interpolation between 2 or 4 data points •

Options O ti tto select l taC Curve ffor 2 points i t or a S Surface f ffor 4 points i t tto d define fi the th parametric space.

Simply enter the 3-D point locations and data values, and Femap does the rest.

25.0 5.0

15.0 10.0

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Lesson 5


Output Map Data Surfaces Maps output from one model as a data surface source for another

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Lesson 5


Other Data Surfaces Mesh Data Surface •

Node / Element ID surfaces

Tabular Data Surface •

2-D / 3-D spreadsheets

•

Multi-dimensional – array of points

•

Linear interpolation

Arbitrary 3-D Data Surface •

Enter Scalar or Vector data

Equation Data Surfaces •

Similar to using Variables

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Lesson 5


Support for Advanced Load Definitions Functions

Variables

Data Surfaces

Force / Forces Per Length / Force Per Area



-

-

Force Per Node / Moment Per Node







Bearing Force

-

-

-

Moment / Moment Per Length / Moment Per Area



-

-

Torque

-

-

-

Displacements p / Rotations / Velocities / Accelerations







Distributed Loads / pressure







Temperatures







H t Fl Heat Flux / H Heatt Fl Flux P Per A Area



-

-

Heat Flux Per Node / Heat Generation / Element Heat Flux







Convection / Radiation







Fluid Loading





Load Type

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Lesson 5


Dynamics Analysis Load Set Options The Model, Load, Dynamic Analysis command sets the Solution Method and dynamic response analysis control parameters for: •

Direct Transient

•

Modal Transient

•

Direct Frequency

•

Modal Frequency

•

Random Response

•

Shock Spectrum Generation

Many of these options can be set and modified using the Entity Editor after a Load Set has been selected using the Model Info tree.

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Lesson 5


Nonlinear Analysis Load Set Options The Model, Load, Load Nonlinear Analysis command sets the Solution for these three types of Nonlinear solutions: •

Static

•

Creep

•

Transient

Many of these options can be set and modified using the Entity Editor after a Load Set has been selected using the Model Info tree.

Note:

After selecting the type of Nonlinear Analysis, click the Defaults button to automatically enter the NX Nastran Nonlinear defaults and modify as needed needed.

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Lesson 5


Heat Transfer Analysis Load Set Options The Model, Load, Heat Transfer command is used for: •

Radiation

•

Free Convection

•

F Forced d Convection C ti

Not required for conduction only models. Many of these options can be set and modified using the Entity Editor after a Load Set has been selected using the Model Info tree.

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Lesson 6

The F Th Femap User U IInterface t f – Part 2

Purpose This lesson provides an introduction to selection, viewing, and data collection tools in Femap’s user interface. Topics •

Select Toolbar

•

View Options

•

Data Table

•

Programming Interfaces

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Lesson 6


Select Toolbar The Select Toolbar allows you to select entities one at a time or create a list of selected entities that will remain active until you toggle off or clear the selection list. This functionality allows you to choose entities of different types first and then perform multiple commands from the menus or the toolbars on the selected entities. The Select toolbar is essential to the use of the dockable panes, especially the Entity Editor and Data Table because the selector is often the best way to place an entity into either of these panes. The Select toolbar consists of 5 items which aid in the selection process: •

Selector Entity Menu

•

Selector Modes Menu

•

Selector Actions Menu

•

Selector Clear (Clear current selection list)

•

Snap Modes (Snap to Screen, Snap to Grid, Snap to Point, Snap to Node)

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Lesson 6


Select Toolbar – Selector Entity This menu allows you to choose which type of entity you would like to select. The current entity type available to be selected will be marked with a check mark in an orange square. The Selector Entity icon visible on the toolbar will change g to the icon of the current entity type being selected. You can toggle this icon back and forth between no selection and the current entity by clicking the icon. The entity types are separated into geometric entities, finite element entities, and text.

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Lesson 6


Select Toolbar – Selector Modes The Selector has different modes to help you select the correct entities, create a “Selection List”, and modify a Selection List. •

Add To Selection - Adds entities to the current selection list when Select Multiple i active is ti or simply i l chooses h entities titi when h Select S l t Si Single l It Item is i active. ti Thi This iis th the default

•

Remove From Selection - Removes entities from the current Selection List when Select Multiple is active. Only allows selection of entities currently in the Selection List. Does not highlight anything when Select Single Item is active

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Lesson 6


Select Toolbar – Selector Modes (continued) Normal - This mode highlights entities which are able to be selected when the cursor is placed over a specific entity. This is the default selection mode. Query - This mode allows you to choose a position on the screen near the entity you wish i h tto select, l t th then “d “drills ill down” d ” into i t the th graphics hi window i d and d selects l t allll th the entities titi th thatt would be touched by an imaginary line perpendicular to the screen. After the entities have been identified, it opens a dialog box and places them in a list for you to choose the correct entity. As you highlight entities in the list, they will be highlighted in the graphics window as well. Once you have found the correct entity, click the OK button. Front - This mode always selects the entity “closest to the front of the screen”. It uses the same premise as Query to “drill down” into the screen with the imaginary line and then simply selects the top-most entity in the current view. If the “top-most” entity is already chosen, it selects the next one along the line, moving into the screen.

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Lesson 6


Select Toolbar – Selector Modes (continued) Select Any Inside - This is a “box” pick mode which signifies that any entity entirely enclosed or has a start or end point within the outline of a selection “box” will be included in the selection. “Box” picking includes Circle, Polygon, and Freehand picking and is only available when Select Multiple is active. Select All Inside - This is the other “box” pick mode which signifies that only entities completely inside the “box” will be included in the selection. Select Related - When this mode is toggled on, it selects ALL other entities that are related to the selected entities and places them in the selection list. To toggle it off, simply select it again. By default this mode is OFF. 

When Select Related is turned on, Select Multiple is also automatically toggled on.

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Lesson 6


Select Toolbar – Selector Modes (continued) Select Single Item - Restricts selection to only one item at a given time. As each entity is selected it will update the Entity Editor dockable pane. This is the default. Select Multiple Items - Allows you to create a Selection List. A Selection List can contain t i multiple lti l entities titi off one ttype or multiple lti l entity tit ttypes. A As each h entity tit is i selected l t d it will update the Entity Editor dockable pane, as well as add the entity to the running totals of the Selection List in the Model Info tree.

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Lesson 6


Select Toolbar – Selector Modes (continued) Show Tooltips - When this mode is activated, a “Tooltip” note will pop up with useful information about the entity which is currently highlighted. To toggle this option off, select it from the menu again. It can also be turned on and off using the right mouse menu in the graphics window, when the Entity Selector is set to None. •

e.g. When entity selection is set to Node, Node the “Tooltip” will ill contain Node number, Coordinates, Definition Coordinate System, and Output Coordinate System. When post-processing, the Contour Output Vector will appear pp in the “Tooltip” p for elements and the Deformation Output Vector will be appear in the “Tooltip” for nodes.



femap101-g-v10.1.1

While a “Tooltip” pop-up window is displaying information, if you click the left mouse button, the information will be sent to the Entity Editor and/or the Data Table dockable panes, as long as the panes are visible in the FEMAP interface AND unlocked.


6- 8

Lesson 6


Select Toolbar – Selector Actions Menu This menu contains “Actions” the Selector can use for specific types of selections. There are various “Box” pick options, grow and shrink commands to build up or cut down a selection, use of the typical FEMAP entity selection dialog box, group commands, copy and paste, and the ability to send a selection over to the Data Table. •

Box - Creates a rectang Bo rectangular lar selection box to pick multiple entities at once. Holding the Shift key also activates this option.

•

Circle - Creates a circular selection “box” to pick multiple entities at once once. Holding the Control key also activates this option.

•

Polygon - Allows you to create a selection area by creating a multisided shape using a click of the mouse to end one “side” of the polygon and begin the next “side”. The polygon can have as many sides as you would like and is very helpful in selecting individual nodes in uniquely shaped geometry.

•

Freehand - Allows you to create a selection area by holding down the left mouse button and “drawing” a freehand sketch. Works very similar to the Polygon mode, but the shape is not limited to the use of only straight lines.

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Lesson 6


Select Toolbar – Selector Actions Menu Coordinate – Select objects by X, and/or Y, and/or Z coordinates by: •

Above or Below a specified value.

•

Outside or Between minimum and maximum values.

•

At Location within a tolerance.

Around Point – Specify a coordinate (In a specified coordinate system) and select by: •

Farther Than or Closer Than a specified radial distance from the point.

•

Outside or Between minimum and maximum values of the specified radial distance.

•

At Location within a tolerance of the specified radial distance.

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Lesson 6


Select Toolbar – Selector Actions Menu Around Vector – Specify a vector and a radial distance from the vector. Select objects: •

Farther Than or Closer Than a specified radial distance from the vector.

•

Outside or Between minimum and maximum distance from the vector.

•

At Location within a tolerance.

Around Plane – Select a plane and the normal distance from the plane. Select objects by: •

Positive Side or Negative Side distance from the plane.

•

Outside or Between minimum and maximum distance from the plane.

•

At Location within a tolerance of the specified distance.

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Lesson 6


Select Toolbar – Selector Actions Menu (continued) Grow - Adds the elements surrounding the currently selected elements to the Selection List. In general, it will start with the selected element and expand out one element in all directions to non-selected elements. The selection will move out an additional element layer every time the Grow command is used Shrink - Removes the outer-most layer of selected elements from the Selection List. Works in the reverse direction as the Grow command.

Initial Selection femap101-g-v10.1.1

1st Growth Iteration

2nd Growth Iteration


6- 12

Lesson 6


Select Toolbar – Selector Actions Menu (continued) Dialog - Brings up the specific FEMAP Entity Selection dialog box for the entity currently active in the selector. This allows you to use all of the entity specific selection methods available on menu when the Method button is clicked inside the dialog box Create Group - Brings up the Save Selection as Group dialog box. Allows you to create a new Group p or to add,, remove,, or exclude the entities in the Selection List from the active Group. Load Group - Allows you to add the entities of any existing Group to the current Selection List. Export Neutral – Takes the objects in the Selection List and writes a Femap Neutral File.

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Lesson 6


Select Toolbar – Selector Actions Menu (continued) Copy - Allows you to copy all of the entities in the Selection List and “Paste “ them into a different model. When the Selection List is copied, the entity data is sent to a modified version of a FEMAP neutral file and is placed on the clipboard. Once on the clipboard, it can be “pasted” into a different model using the Paste command on the Selector Actions menu (Ctrl+v will not work in this case) •

You MUST be ssure Yo re that all entities related to a specified entity are included in the Selection List before using the Copy command. This will assure an accurate transfer between models occurs. One way to assure a Selection List will be complete p for copying py g purposes is to use the Select Related mode of the Select toolbar.

Paste - This command allows you to “paste” a copied Selection List into a another opened Femap model. The Paste command recognizes that a modified FEMAP neutral file is on the clipboard and reads that neutral file into FEMAP. •

When the Paste command is used it will bring up the Neutral File Read Options dialog box to allow you enter an ID offset and select other options to aid in the prevention of overwriting entities in the current model.

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6- 14

Lesson 6


Select Toolbar – Selector Actions Menu (continued) Add to Data Table - Takes all of the entities in the Selection List that are the entity type currently active in the Selector and sends their data to the Data Table. The Data Table MUST be “unlocked” in order for this command to be available.

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6- 15

Lesson 6


Select Toolbar – Context Sensitive Menus While a certain entity type is active in the selector, only that entity type will be available for picking in the graphics window. Since FEMAP is only highlighting one specific entity type at a time, there are context sensitive menus for each entity type (except Text). These menus can be accessed by highlighting an entity in the graphics window and then clicking the right mouse button. These Context Sensitive menus contain frequently used commands for each entity type.

Any time there is an active entity in the Select Toolbar, clicking Alt + clicking the right mouse button in the graphics window will bring up the Quick Access Menu instead of the context sensitive menu related to the active entity. This can very helpful for picking mode purposes and to toggle Show Tooltips.

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6- 16

Lesson 6


Select Toolbar – Clear Selector Options Select Toolbar has two options for clearing a Selection List: •

Clear All – clears the entire Selection List

•

Clear Active Entity – clears only the active Selector Entity

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6- 17

Lesson 6


View Options The View, Options (F6 hotkey) command allows you control the way your view is displayed. There are three major categories in the View Options dialog box: •

Labels, Entities and Color – controls the way text, geometry and mesh entities, and the color of entities are displayed in the active view.

•

Tools and View Style – controls view entities, style and display of view objects such as Symbols in the active view.

•

PostProcessing – controls the options for displaying graphical and XY plots of analysis results.

See the View Options section of the Femap Commands manual for details on the multiple options available in these dialog boxes.

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6- 18

Lesson 6


View Options (continued) The view background can be modified with the View, Background command. With this command, you can specify a background that is either •

Transparent

•

Solid

•

Shaded

•

You also have the option to specify a bitmap as a logo background. The bitmap for the logo is specified in the Femap Preferences dialog box in the Views tab.

A view with its View Options, Entity Display settings, and Background can be saved to a View Library within the Visibility dialog box (activated with the Ctrl Ctrl+Q Q hotkey or from the View toolbar) by clicking the Save View button. •

A saved view will update the active view’s settings by clicking Load View.

•

Changes g made to the active view can also be removed via the Reset View button in this dialog box.

Saved views can also be set as the Startup View for all new models via the View tab of the FEMAP Preferences.

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Lesson 6


Data Table Use the Tools, Data Table command or the Panes toolbar to turn the Data Table on and off. •

When the Data Table is first opened, it is “locked”. The Lock/Unlock icon must be p data. selected to unlock it to enable it to receive or update

Data is placed into an interactive, dynamically changing “table” using various methods to fill the table provided it is unlocked 

Each item appears as a single row separated into a number of columns when it enters the Data Table.



Information of entities of the same type can be sorted, filtered, and evaluated to help you understand d d what h iis occurring i iin your model d lb before f and d after f analysis. l i



In many ways, the Data Table is a complement to the other dockable panes and can also simply be an alternate method to list and view entity data

All FEMAP entities which can be selected using the Select toolbar can be sent to the Data Table. Several commands are available for listing and sorting results when the Data Table is open and analysis results sets are loaded into your FEMAP model: 

List, Output, Summary to Data Table



List, Output, Results to Data Table



List, Output, Nodal Changes to Data Table

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Lesson 6


Programming Interfaces Program Files •

FEMAP has the ability to record and replay command sequences using Program Files.

•

Program Files can be edited to accept user input input.

•

Program Files may not be compatible between different versions of FEMAP.

API – FEMAP has an Application Programming Interface that can be used to customize FEMAP for applications such as: •

Automate tasks such as swapping the background colors of views for printing .

•

Calculate the midplane stresses on shell elements elements.

•

Interface with other programs for the purposes for importing, modifying, or reporting data.

•

FEMAP has a built-in Basic language programming environment through the API Programming pane. •

Microsoft Visual Basic and Visual C++.NET can also be used to develop custom applications li ti ffor FEMAP FEMAP.

•

The API can be used to embed FEMAP into other applications; open, create, and/or modify FEMAP models; or to develop standalone FEMAP applications without using FEMAP’s GUI.

•

Examples of API applications are shipped with FEMAP in FEMAP’s API folder. The Custom Tools toolbar is set by default to point to this folder.

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Lesson 7

M d l Di Model Display l and d Vi Visualization li ti

Purpose This lesson provides an introduction to selection, viewing, and data collection tools in Femap’s user interface. Topics •

Geometry, Material, Property and Layer Visibility Toggles

•

View, Advanced Post, Model Contour Data command

•

Comparing Groups and Layers

•

Layers

•

Groups

•

View Options

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7-1

Lesson 7


Geometry, Element, Material and Property, Display Control Beginning with Femap Version 10.1, display of Element (by Type or by Shape), Materials, Properties and can be controlled from the Model Info pane. Femap v10.1.1 adds the ability to toggle solids on and off. •

j ID/name is the Visibilityy Toggle gg and indicates The box to the left of the object’s whether or not the object is displayed. •

Indicates that the object is displayed.

You can also select one or more of the same object type and then Right-click to bring up the Visibility Toggle menu. Femap will display the combination of selected geometry, geometry element types types, materials materials, properties and groups, eliminating the need to organize the model by layers or by creating additional groups.

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Lesson 7


Display Control Example Example: Wing model with multiple groups, element types and shapes, materials and properties.

Model Tree:

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7- 3

Lesson 7


Display Control Example (continued) Display only portion of the model with elements comprised of Aluminum alloys:

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7- 4

Lesson 7


View, Advanced Post, Model Contour Data Command Beginning with Femap v10.1, the View, Advanced Post, Model Contour Data command is available. This command is also directly available on the View toolbar.

With this command, you can display Contour, Criteria, or Beam Diagram plots of model data such as in the example below where Plane Element Thickness is shown as a contour plot plot. •

You cannot simultaneously display model data and analysis results.

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7- 5

Lesson 7


Comparing Groups and Layers

Layers

Groups

Can be assigned to multiple Groups

Entities

Display Simultaneously?

Can be assigned to only one Layer

Assign by rules, relationships, and/or clipping.

Imported with some CAD geometry t formats. f t

Automatic generation tools.

Multiple / User Controlled

Reference Groups for managing “groups” of Groups (Femap v10.1)

Multiple / User Controlled (single Group only prior to Femap v10.1)

Displayed Layers only Graphical Selection

femap101-g-v10.1.1

Optional “No Pick” layer prevents g p graphical p selection of entities on that layer (except when Select All is used).

Only entities in the displayed groups can be selected except when Select All is used.


7- 6

Lesson 7


Layers Create new layers using the Tools, Layer command. The Layer Manager dialog box:

•

Create New Layer y •

Assign ID, Title and Color •

View Options allows display of colors by layer (by entity type)

•

Modify the name of a layer using the Update button

•

Renumber layer(s)

•

Delete layer(s)

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7- 7

Lesson 7


Layers and the Model Info Tree Layer objects 

New layers

• Activate layers • Manage M l layers • Delete layers • Manage visibility

Selection List objects 

Modify layer

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7- 8

Lesson 7


Defining and Populating Groups Define using commands on Group menu •

Use the Group, Create/Manage command to create a Group, then use other commands to add entities into group

Group Rules •

Various entity selection commands, either by ID or using relationships to other entities

•

Entities can be added to group using any combination of selection methods

•

When selecting entities, use the Exclude option if you want the selected entities removed permanently from the group.

Group Clipping •

Selects all entities inside/outside clipping region

•

Set Clipping first, then rules.

Referenced Groups allow a group to link to one or more other group(s).

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7- 9

Lesson 7


Control of and Automatic Generation of Groups The Group, Operations command set: • Use Automatic Add to add to the either the Active or Selected group as you model • Evaluate and Evaluate Always are used to update groups as the model is modified. • Limit Li it use off Evaluate E l t Always Al i llarge models. in d l • Copy and Condense groups • Combine groups using Boolean operations • Use Add Related Entities to add entities to existing groups such as Loads and Constraints on Surfaces, Nodes on Elements, etc. • Generate commands can be used to automatically generate and maintain groups in the model by: • Solids • Property • Material • Element Type • Output • Superelements • Layers

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7- 10

Lesson 7


Using Booleans with Groups The Group, Operations, Booleans command allows you to create a new group: •

Add / Combine – take all entities from the selected groups.

•

In all – take entities that are common to all of the selected groups.

•

N t iin Any Not A – take t k entities titi that th t do d nott exist i t in i any off the th selected l t d groups.

•

Subtract – remove the entities from the selected groups from another group.

•

Only in One - take only the entities that exist in one of the selected groups.

•

Not in All - take only the entities from the selected groups that do not exist in all of the selected groups.

Note: To see examples of the Group, Operations, Booleans command, go to Section 6.4.3.2 of the Femap Users Guide.

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Lesson 7


Group Creation and Control from the Model Info Pane Right-click on a group name to bring up the contextsensitive menu for groups. •

group p Create a New g

•

Combine groups into a new group

•

Add Related Entities

•

Toggle Automatic Add to the Active or Selected group

•

Show the Full Model, Active Group or Multiple Groups (a further explanation of this follows).

•

Activate the selected group

•

List the contents of the selected group(s)

•

Delete the selected group(s)

•

Manage Referenced M R f d Groups



Add to Selection – adds the contents of the selected group(s) to the Selection List



Export Neutral exports the contents of the selected group(s) to a Femap Neutral file

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Lesson 7


Group Display Control Beginning with Femap Version 10.1, multiple groups can be displayed using either the View Visibility dialog box or via the Group tree in the Model Info pane. To activate the Visibility dialog box to control display of groups: •

Click the View Visibility icon on the View toolbar or

•

Right-click in the graphics window and select Visibility on the context-sensitive menu

•

Select the Group tab in the Visibility dialog box

•

Choose between: •

Show Full Model – when selected, the selection of individual groups in the group list section of this dialog box is grayed out.

•

Show Active Group

•

Show Single Group – when selected, the selection of individual groups in the group list section of this dialog box is grayed out.

•

Show/Hide Multiple Groups

•

The box to the left of the group’s ID and name is the Visibility Toggle and indicates whether or not the group is displayed.

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Lesson 7


Group Display Control (continued) The display of groups can also be controlled from the Group tree in the Model Info pane. •

The box to the left of the group’s ID and name is the Visibility Toggle and indicates whether or not the group is displayed. •

Indicates that the group is displayed.

•

Indicates that the group is hidden.

•

A blank checkbox also indicates that the group is not displayed.

•

Indicates that all groups are displayed.

You can also select one or more of the same object type and then Right-click the Visibility Toggle.

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Lesson 7


Group Display Control Using the Status Bar Tray In addition to the Model Info pane’s Group tree, you can activate a group using the Status Bar Tray •

Click “Grp: (#)” on the Status Bar Tray and select the group you want to activate. •

•

The number (#) indicates the active group number

Groups can also be created and managed by selecting the Create/Manage option from this menu.

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Lesson 7


View Options In many cases, you may want to display specific entity indicators such as surface normal, curve direction or element normal's. The View Options dialog box offers options to display these indicators. Example E l – Turn T on display di l off rigid i id elements l t d degree off ffreedom d iindicators di t and d master/slave nodes:

An unfilled box indicates the Slave Node on the rigid element

A filled box indicates the Master Node on the rigid element

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Lesson 7


View Options (continued) Example– Turn on display of surface normal's:

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7- 17

Lesson 8

M hi O Meshing Overview i

Purpose This lesson provides an overview of the tools available in Femap to control and generate meshes. Topics •

Recommended Meshing Workflows

•

Mesh Control

•

Feature Suppression

•

Geometry Meshing

•

Hex Meshing

•

Mesh Modification Tools

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8-1

Lesson 8

Meshing Overview

Recommended Meshing Workflows Before any meshing, set a reasonable Default mesh size for the model then set the mesh sizing for the objects to be meshed

Break edge curves where needed Create any needed Curves on Surfaces and Mesh Points on Surfaces Solids

Suppress any features as needed Set the Mesh Size on Solids Assign solid Attributes Set the mesh size on individual surfaces as needed

Break surface boundary curves where needed Create any needed Curves on Surfaces and Mesh Points on Surfaces Surfaces

Suppress any features as needed Set the Mesh Size on Surfaces Assign surface Attributes Mesh the selected surfaces Set the mesh size on individual curves as needed

Break curves as needed Curves

Set the Mesh Size on Curves Assign curve Attributes

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8-2

Lesson 8

Meshing Overview

Mesh Control The Mesh, Mesh Control menu creates settings for: •

Default mesh size

•

Set mesh size on curves, surfaces and solids

•

“Hard” mesh points

•

Mesh Attributes - assignment of element properties to geometry

•

Mesh approaches on surfaces

•

Suppression of geometric features during meshing

Many of these commands are also on the Mesh toolbar.

Preview mesh sizing on curves with the View, Options (F6), (F6) Labels, Labels Entities and Colors, Colors Curve – Mesh Size option •

Toggle Mesh Size symbols with the View Style, Mesh Size icon on the View toolbar.

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Lesson 8

Meshing Overview

Mesh, Mesh Control Commands Mesh, Mesh Control, Default Size •

Used to define the default element size.

•

If you only need a uniform mesh, this will be the only mesh control operation you need to do do.

•

Used along curves that have no other sizing specified.

Mesh, Mesh Control, Size commands •

At Point, used to specify the size along any curve that references that point, and does not already have a size specified.

•

Along Curve, specifies the element size, or number of elements to be placed, and how they will be spaced along the curve curve.

•

On Surface, used to specify the size on all of the curves referenced by the surface, and gives other options for controlling the mesh on the surface.

•

On Solid, provides the same basic mesh control as the previous, but also has additional options that pertain primarily to multi-solid meshing, and hex meshing.

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8-4

Lesson 8

Meshing Overview

Mesh, Mesh Control Commands (continued) Mesh, Mesh Control, Interactive, allows you to interactively modify existing mesh sizes along one or more curves. •

Add: The current curve mesh size is increased by the number of elements p specified

•

Subtract: The current curve mesh size is decreased by the number of elements specified. It is not reduced below 1

•

Set To: The curve mesh size is set to the number of elements specified

Note:

Interactive sizing g with automatic re-meshing g is available in the Meshing g Toolbox under the Mesh Sizing toolset.

Mesh, Mesh Control, Custom Size Along Curve, can be used to place nodes at specific locations along curves, and match one curve's mesh sizing to another curve or curves. •

See example on following pages

Mesh, Mesh Control, Mapped Divisions on Surface, allows you to specify divisions for a mesh on 3 and 4 sided surfaces Mesh, Mesh Control, Mesh Points on Surface, defines specific locations on a surface where nodes will be created when the surface is meshed

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8-5

Lesson 8

Meshing Overview

Example - Mesh, Mesh Control, Custom Size along Curve

Surface Mesh Size = 5 with Mesh Size of 8 applied to arc on upper boundary of surface

Custom Mesh Size along Curve command applied to the single lower boundary of the surface by Matching the three curves on the upper boundary of the surface femap101-g-v10.1.1


8-6

Lesson 8

Meshing Overview

Example p - Mesh,, Mesh Control,, Custom Size along g Curve (continued)

Resulting mesh after applying the Mesh, Mesh Control, Custom Size along Curve command

femap101-g-v10.1.1


8-7

Lesson 8

Meshing Overview

Mesh, Mesh Control Commands (continued) Mesh, Mesh Control, Attributes •

At Point, used to assign meshing properties to points, so that when the points are meshed, the properties will automatically be assigned to the points

•

Along Curve Curve, in addition to specifying the property to be used used, there are additional options, like element orientation, releases, and offsets

•

On Surface, most commonly used for assigning plate properties to surfaces, and should be used when meshing multiple surfaces with different properties in one meshing operation. •

•

Includes ability to pre-assign plate offsets to surface

O Volume/Solid, On V l /S lid are much h th the same as th the above, b only l applies li tto volumes/solids l / lid

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8-8

Lesson 8

Meshing Overview

Mesh, Mesh Control Commands (continued) Mesh, Mesh Control, Approach on Surface, used to specify whether FEMAP will create a free/boundary mesh or a mapped mesh. There are several options for free and mapped meshing. For details, see section 5.1.1.15 in the Femap Commands Manual •

pp primarily y uses the Free-Parametric approach pp for meshing g Femap

•

Beginning with Femap v10.1.1, Femap can automatically assign the corner points when the Mapped – Four Corner option is selected

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8-9

Lesson 8

Meshing Overview

Setting Mesh Sizing on Surfaces Use the Mesh, Mesh Control, Size on Surface command. • Select the Replace Mesh Size on All Curves option to override mesh sizes on any curve that has had it’s mesh size set curve mesh sizing command(s). • Use Min Elements on Edge to set the number of elements on curves with their length less then the Element Size setting.

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8 - 10

Lesson 8

Meshing Overview

How Femap determines Element Size For both solids and surfaces, Femap provides a recommended Element Size by dividing the average length of the curves on the selected surface or solid by 6.

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8 - 11

Lesson 8

Meshing Overview

Max Angle Tolerance Max Angle Tolerance controls the maximum allowable angle between the tangent of a surface’s boundary curve at the start of the element edge and the angle of the free edge of the element. With this option enabled, the length of all free edges on the selected surface(s) must be less than or equal to the Element Size.

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8 - 12

Lesson 8

Meshing Overview

Setting Mesh Sizing on Surfaces (continued) Max Elem on Small Feature and Max Size of Small Feature are used to control the number of elements around the perimeter of an interior boundary. •

Max Size of Small Feature is the effective diameter of the interior feature calculated g of the p perimeter length g of the interior feature divided by yp pi. byy taking •

The default value of this option is equal to the value of the Element Size.

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Lesson 8

Meshing Overview

Vertex Aspect Ratio Vertex Aspect Ratio is used to optimize mesh sizing at locations where both long and short curves are joined at common vertices

Initial Mesh – Vertex Aspect Ratio Option Disabled Jacobian Mesh Quality Displayed

Initial Mesh – Vertex Aspect Ratio = 2.0 Jacobian Mesh Quality Displayed femap101-g-v10.1.1


8 - 14

Lesson 8

Meshing Overview

Mapped pp Meshing g Refinement and Suppress pp Short Edges g Options The Mapped Meshing Refinement option attempts to refine the mesh for 3 or 4-sided surfaces. Suppress Short Edges suppresses any edge on the selected solid(s) or surface(s) that h a llength has th lless th than or equall tto th the specified ifi d percentage t off th the Element El t Si Size. •

Suppressing short edges on certain solids or surfaces may cause the mesher to fail. While not common, an error stating you have a "hole" in the mesh will inform you of this situation.

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8 - 15

Lesson 8

Meshing Overview

Parameter vs. Length Based Mesh Sizing Femap, by default, uses Parameter mesh sizing. For many cases, there will be no difference between Parameter and Length-based mesh sizing, however, for complex curves and surfaces such as splines, there is a difference:

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8 - 16

Lesson 8

Meshing Overview

Curvature Based Mesh Refinement The Curvature Based Mesh Refinement option, Refinement Ratio is similar to Max Angle Tolerance except it uses a length ratio instead of angles •

Refinement Ratio = Chord Height / Chord Length •

Chord Height = maximum normal distance from the element edge to the curve or surface

•

Chord Length = length of the element edge

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8 - 17

Lesson 8

Meshing Overview

Setting Mesh Sizing on Solids Use the Mesh, Mesh Control, Size on Solid command. •

Similar to the Automatic Mesh Sizing dialog box for surfaces except for addition of the selection of either Tet Meshing or Hex Meshing, and the Auto Boundary y / Multi-Solid Sizing g options. p Small Surf and Assembly

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8 - 18

Lesson 8

Meshing Overview

Auto Boundary Small Surf Auto Boundary Small Surf attempts to combine any surface on a solid that has a area less than or equal to the specified percentage of Element Size squared with an adjacent surface that is tangent or nearly tangent to the small surface.

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8 - 19

Lesson 8

Meshing Overview

Assembly / Multi-Body Sizing The Assembly / Multi-Body Sizing options can be used to automatically set mesh approaches on solids with adjacent surfaces when multiple bodies are selected .

•

Adjacent Surface Matching – when surfaces on two adjacent bodies are coincident and have sizes and boundaries, Femap will slave the mesh size and approach of the two surfaces.

•

Use the Remove Previous Slaving option to remove the mesh sizing and slaving on bodies that have had mesh sizes previously applied.

•

Adjust Colors changes the colors of surfaces that have mesh sizes set set. The following lists the colors and their meanings:

•

•

Dark Transparent Blue – free surfaces that have mesh sizes successfully applied.

•

Light Solid Blue – surfaces that have been matched to an adjacent surface for the purpose of creating a continuous mesh.

•

Red – surfaces on solids that cannot be hex meshed.

Skip Sizing on Slaved Surfaces – skip mesh sizing on surfaces that are slaved to another surface.

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Lesson 8

Meshing Overview

Surface Mesh Approach: Free Mesh The Mesh, Mesh Control, Approach on Surface command allows you to set the method for meshing surfaces (including surfaces on solids). •

If not specified, Femap will use either the Free/Parametric or Mapped – Four corner pp based on g geometry y and resulting g mesh q quality. y approach

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Lesson 8

Meshing Overview

Surface Mesh Approach: Mapped – Four Corner

Mapped Four Corner Mesh – Example 1

Mapped Four Corner Mesh – Example 2 femap101-g-v10.1.1


8 - 22

Lesson 8

Meshing Overview

Surface Mesh Approach: Mapped – Three Corner

M Mapped d Three Th Corner C Mesh M h

Mapped Three Corner Fan Mesh

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8 - 23

Lesson 8

Meshing Overview

Edge and Feature Suppression Use the command, Mesh, Mesh Control, Feature Suppression •

Removing Loops works on surfaces and solids.

Interactive feature suppression is also available in the Meshing Toolbox under the Feature Suppression toolset.

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8 - 24

Lesson 8

Meshing Overview

Boundary Surface from Surfaces on Solid The command, Geometry, Boundary Surface, From Surfaces on Solid •

Takes the surfaces you select, and uses the enclosing outer curves to form a regular boundary surface.

•

The surfaces must be stitched into a solid solid.

•

This feature works best with surfaces that have small to moderate curvature.

•

Can be used to remove sliver surfaces by selecting surfaces that surround the sliver.

•

This capability is also found in the Meshing Toolbox under the Combined/Boundary Surfaces toolset.

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Lesson 8

Meshing Overview

Geometry Meshing Mesh, Geometry, Point - is the most basic of the automatic meshing commands. •

Will generate nodes (and elements for 0D element types such as Mass Elements) at the selected points.

•

Allows you to specify the beginning node and element ID ID.

Mesh, Geometry, Curve •

Creates a mesh of nodes and 1-D elements along a curve

Mesh, Geometry, Surface - creates nodes and planar elements on a selected set of surfaces. •

Must first define the mesh sizing using one of the various Mesh Control commands

•

There are also basic Mesh Control options on the Automesh form, as well as Mesh Smoothing, and Element Shape options

Mesh, Geometry, Volume - creates nodes and elements in a selected set of volumes. •

Since this command uses a mapped meshing technique, the number of nodes/elements / along opposite faces f off a volume must always be equal

Mesh, Geometry, Solid - Produces a 3-D solid tetrahedral mesh in a solid part Mesh, Geometry, Solids From Elements - meshes a plate element mesh that encloses a volume into a solid element mesh

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Lesson 8

Meshing Overview

Automesh Surfaces Dialog Box The Mesh, Geometry, Surfaces command opens the Automesh Surfaces dialog box. By default only a portion of the available mesh options are visible.

You may specify the following options: •

Mesher – Triangle or Quad

•

Toggle generation of Midside Nodes

•

Toggle Mapped Meshing on or off

To see all of the surface meshing options available, press the More Options button.

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Lesson 8

Meshing Overview

Automesh Surfaces Dialog Box The expanded Automesh Surfaces dialog box has the following options: •

Mesher – Triangle or Quad •

•

Toggle generation of Midside Nodes •

•

Pre-V10 Meshing can be used to have FEMAP mesh using the “old” meshers and options options. Connect Edge Nodes and a Tolerance can be set to automatically merge nodes on surfaces of stitched bodies.

Toggle Mapped Meshing on or off and set various mapped meshing options.

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8 - 28

Lesson 8

Meshing Overview

Automesh Surfaces Dialog Box Expanded Automesh Surfaces dialog box (continued):

•

•

Select the Smoothing option and settings to reduce mesh distortion. •

Laplacian moves the node towards the centroid of the surrounding nodes.

•

Centroidal moves a node towards the centroid of the element-weighted centroid of the surrounding elements.

Offset options allow you to offset to the top face, bottom face, or by a specified value as the mesh is created instead of having to do it as a secondary step. •

If an offset is applied as part of the Mesh, Mesh Control, Attributes on Surface command, that value will be used if no value is set in the Automesh Surfaces dialog box. If a value is entered, it will override the previously set attribute value.

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8 - 29

Lesson 8

Meshing Overview

Automesh Surfaces Dialog Box Expanded Automesh Surfaces dialog box (continued):

•

Post-Meshing Cleanup is on by default and detects certain patterns in the mesher to eliminate them

•

Cut Quads with Angle Deviation Above specified degrees

•

Min Elements Between Boundaries forces the mesher to attempt to put the specified number of elements between adjacent boundaries

•

Max Element Aspect Ratio attempts to create elements which are under the specified aspect ratio

•

Quick-Cut boundaries… splits boundaries with more then the specified number of nodes into smaller pieces for meshing.

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Lesson 8

Meshing Overview

Quad Edge Layer Option for Quad Meshing of Surfaces •

Use the Quad Edge Layer option to set the “depth” of quad elements around features

0 Layers

femap101-g-v10.1.1

1 Layer

2 Layers


3 Layers

8 - 31

Lesson 8

Meshing Overview

Automesh Solids Dialog Box When applying the command, Mesh, Geometry, Solids, the Automesh Solids dialog box is activated. With this dialog box, you specify the following options: •

Surface Mesh Only

•

Toggle Midside Nodes

•

Tet Growth Ratio – specify a factor to increase the size of the interior elements over the size of the initial surface mesh.

•

Initial Size Ratio – used to provide additional control for the size of the mesh. Lower values results in denser meshes.

•

Update Mesh Sizing – activates the Automatic Mesh Sizing dialog box for solids.

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Lesson 8

Meshing Overview

Manual Meshing Tools Model, Element command. •

Creates a single element

Mesh, Between command. Mesh, Region command. Mesh, Revolve, Extrude and Sweep commands. •

With these commands you can revolve , extrude, or sweep curves or line elements into plane elements, and plane elements into volume elements. You can also select face(s) on volume element(s) to create additional volume elements.

Mesh Copy, Radial Copy, Scale, Rotate and Reflect commands.

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Lesson 8

Meshing Overview

Manual Mesh Modification Tools Mesh, Editing, Interactive command.

Mesh, Editing, Split command.

Mesh, Remesh command set. Mesh, Smooth command.

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Lesson 8

Meshing Overview

Semi-Automatic Hex Meshing Femap can automatically hex mesh solids that are valid mapped meshing solids (solids of extrusion or revolution) Preparing the solid for Hex Meshing •

Begin by slicing the solid into simple sections that are extrusions using the following commands: •

Geometry, Solid, Slice

•

Geometry, Solid, Slice Match

•

Geometry, Solid, Slice Along Face

•

Geometry Solid, Geometry, Solid Embed Face

Meshing the Solids •

Use Mesh Control to set the size and link the adjacent surfaces

•

Then Mesh, Geometry, Hex Mesh Solids

Note:

Solids of revolution must be sliced so that the solid comprises is less then a 360-degree revolution. e.g A straight, pipe section must be split in half.

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Lesson 8

Meshing Overview

Meshing Toolbox In a later section, you will learn about the Meshing Toolbox. This toolbox allows for interactive modification of geometry and meshes to improve the quality of meshes: •

Geometry Feature Suppression

•

Geometry Feature Removal

•

Geometry Combined/Composite Curves

•

Geometry Combined/Composite Surfaces

•

Mesh Sizing Toolbox

•

Mesh Locate Toolbox

•

Mesh Quality Toolbox

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8 - 36

Lesson 9

A l i S Analysis Sett M Manager

Purpose This lesson provides an introduction to the setup of analyses using Femap’s Analysis Set Manager. Topics 

The Analysis Set Manager



Analysis Set Manager Dialog Box



NX Nastran Supported Solution Sequences



NX Nastran Input File Setup



Preview/Edit Input



Bulk Data Entries



Analyze Process



NX Nastran Analysis Procedure and Files

femap101-g-v10.1.1


9-1

Lesson 9


The Analysis Set Manager Femap’s Analysis Set Manager manages the options necessary to: •

Create a ready to run input file.

•

Launch the NX Nastran solver or to launch another locally installed solver.

•

St t VisQ Start Vi Q to t send d the th input i t file fil to t a solver l on another th machine. hi

Analysis Sets are stored along with the Femap model file or can be stored in a Femap library that is available across different model files. To enter the analysis Manager select the Model, Analysis command. •

Click the New button to create a new Analysis Set. •

Specify a Title, Analysis Program, and the Analysis Type

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9-2

Lesson 9


NX Nastran Supported Solution Sequences Linear statics Normal modes Buckling Dynamics •

Modal or direct transient

•

Modal or direct frequency

•

Response Spectrum

•

Random Response

Design optimization Nonlinear •

Nonlinear statics

•

Nonlinear transient response

Heat Transfer •

Steady-state heat transfer

•

Transient heat transfer

Advanced Nonlinear •

Nonlinear Statics (SOL601,106)

•

Nonlinear Transient (SOL601,129)

•

Nonlinear Explicit (SOL701)

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9-3

Lesson 9


Analysis Set Manager Dialog Box The Analysis Set Manager dialog box shows all analysis sets defined in the model •

Expand the tree view with +,-

•

Edit sets by double click on tree item or highlight and select Edit button

•

E Export: t writes it input i t file fil tto di disk k

•

Delete

•

Copy

•

Load and Save to the Analysis Set library

femap101-g-v10.1.1


9-4

Lesson 9


NX Nastran Input File Setup Select Solver and Analysis Type Set Executive, Bulk Data, GEOMCHECK, MODELCHECK options •

Can add additional NX Nastran cards and/or Include Files with Start/End Text options

Case Control •

Master Requests and Conditions

•

Subcases •

Select Master Requests and Conditions then click the New button

Multi set: •

Select constraint and loads sets and Femap will create a subcase for each combination of selected constraint and load set(s)

•

Not available for all analysis types

femap101-g-v10.1.1


9-5

Lesson 9


Analysis Set – Nastran Bulk Data Options Dialog Box When using one of the Nastran solvers, the Nastran Bulk Data Options dialog box has multiple options. Two of the many options are described below. See section 8.7.1.3 of the Femap Commands Manual for more details. •

y onlyy a portion p of the model,, yyou can specify p y a single g g group p to If yyou want to analyze write out only with the Portion of Model to Write option.

•

Some models may have specified the mass properties entry for materials as weight density rather then mass density. In this case, enable the WTMASS option and specify the value of the gravitational constant.

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Lesson 9


NX Nastran Advanced Dynamics Options NX Nastran Advanced Dynamics has additional options for the selected analysis Type in the Analysis Set

These options can also be defined in a Load Set.

femap101-g-v10.1.1


9-7

Lesson 9


NX Nastran Nonlinear Options When NX Nastran Nonlinear is the analysis Type, Nonlinear options can be set as part of the Master Request and Conditions or as an option when subcases are used. •

Just like in NX Nastran Advanced Dynamics, these can also be set as options in a load set.

femap101-g-v10.1.1


9-8

Lesson 9


Preview/Edit Input Preview •

Generates the input deck

•

Check for errors

Edit Preview •

Modify, add, remove entries

•

Standard field spacing displayed as header

•

Add comments

Analyze or Export

femap101-g-v10.1.1


9-9

Lesson 9


Analyze Process Analyze operation •

Exports input deck and starts in a NX Nastran job p p process as a separate

•

The Analysis Monitor displays the NX Nastran .log, .f04, or .f06 files

•

Results automatically loaded into Femap ((Femap p Preferences default).

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9 - 10

Lesson 9


NX Nastran Analysis Procedure and Files NX Nastran Output files – these files are retained : • .f06 (Print File) – Contains results data, as well as, warning and error messages. Also, XY Plot data, diagnostic information (Geomcheck, Weight Check, Ground ), Grid point p force data,, and Failure indices for Composite p (Laminate) ( ) Elements Check), prior to Femap 8.3 • .op2 (Binary Output File) – Contains results data in binary format, but results data can be imported into Femap much faster using the .op2 • .f04 (Text File) – Contains a summary of file and database usage information, memory and disk usage sizes, and module execution and statistical information. • .log log (Text File) – License usage, usage summary of solution times times, and other general information about the execution of NX Nastran. Results data: • Components of displacements at grid points • Element Recovery data (stresses, strains, strain energy, and internal forces and moments • Grid point data recovery (applied loads, constraint forces, and element forces)

Note:

Several temporary files are generated during an NX Nastran analysis execution. By default, these files are placed in the scratch file location designated during the installation of NX Nastran. These files are automatically deleted after the successful execution of NX Nastran. Femap allows you to override the default scratch file through a preference setting, or you can specify the file location in an Analysis Set option. The scratch file folder should be checked frequently q y and files deleted as needed.

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9 - 11

Lesson 10

Visualizing Vi li i and dD Documenting ti Results

Purpose: This lesson provides an overview of post-processing results in Femap.

Topics: 

View Select Command



Deformed and Contour Data



Contour Options



Nodal vs. Centroidal Stresses



Output Transformations



Animation Commands and Options



XY Plots



Freebody Display



Vector Plots



Detailed Post Processing Options



Post Processing Toolbar

femap101-g-v10.1.1


10 - 1

Lesson 10

Visualizing and Documenting Results

View Select Command The View Select dialog box: 

Specify the Deformed style • Deformed • Animation A i ti • Vector • Trace



Specify the Contour style • Contour • Criteria • Beam Diagram • IsoSurface • Section Cut • Vector



Select Deformed and Contour Data to select data, e.g., g von Mises Stress

Review Femap User Guide – Chapter 5.9.1 – Working with View Select and View Options

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Lesson 10


Deformed and Contour Data To select the results data to display, activate the Select PostProcessing Data dialog box with the View, Select command or by right-clicking in the graphics window and selecting the Post Data command. M t have Must h results lt available il bl iin F Femap Key items to specify •

Output Set

•

Deformation Output Vectors

•

Contour Output Vectors

•

Contour Options

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10 - 3

Lesson 10


Contour Options The contour algorithm in Femap will use either nodal or elemental data to perform the contouring. •

Depending on the selected options and the available data, Femap will use several pp to calculate the contours different approaches



Contour Group – allows the display of results of the Active or Selected group without activating the group.



Data Conversion options





Average, Use Corner Data (default)



Average, without Corner Data



Maximum Value – with or w/o Corner Data



Minimum Value– with or w/o Corner Data

Element options 

Provides the capability to “Smart Average” results Thus results. accounting for discontinuities in material or geometry and providing a more accurate representation of the results.



Option to display Double-sided Planar Contours on planar elements

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Lesson 10


Nodal vs. Centroidal Stresses Output data from analysis programs varies in the position that it is calculated •

Nodes or the centroid of the element

If you select nodal data, e.g., translations, Femap uses it directly For results with element centroid data but no corner data, you can either: •

Average the Centroidal values for the all the elements connected to each node (default); or

•

Use the Maximum of the Centroidal values of the connected elements.

For results with element centroid data and element corner data you can either: •

Average the values at each node (element corner data) to determine the data (default),

•

Use the maximum of the values at each node (element corner data)

•

Average the Centroidal values for the all the elements connected to each node (ignores the corner data you have); or

•

Use the Maximum of the Centroidal values of the connected elements.

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Lesson 10


Example – Nodal Data Conversion Example: • Four elements sharing node “N”, with corner data • Stress at node N can be calculated A Average with ith and d without ith t C Corner D Data t • with:

σN = (σW+ σX+ σY+ σZ)/4

• without:

σN = (σA+ σB+ σC+ σD)/4

Maximum Value with and without Corner Data • with:

max (σW, σX, σY, σZ)

• without:

max (σA, σB, σC, σD)

Minimum Value with and without Corner Data • with:

min (σW, σX, σY, σZ)

• without:

min (σA, σB, σC, σD)

femap101-g-v10.1.1


Node “N”

10 - 6

Lesson 10


Example – Nodal Data Conversion

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10 - 7

Lesson 10


Output Transformations By default, Femap displays NX Nastran results in the global or “basic” rectangular coordinate system. The Select PostProcessing Data dialog box has options to transform output vectors to user-selected directions.

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Lesson 10


Output Transformations (continued) In this example, we want to display the radial stress and deformations around the large hole. A radial coordinate system is centered at the large hole.

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10 - 9

Lesson 10


Animation Commands Create the animation in the View Select dialog box and select Animate as the Deformed Style This will create an animation of the active Deformation Output Vector in the Deformed and Contour Data Dialog Box •

By selecting the View, Advanced Post, Animation command, you can control the speed of the animation.

•

Once the plot is Animating it can be saved as an AVI file or Animated Gif file (*.GIF) using the File, Picture, Save command and selecting the “Video for Windows (*. AVI)”or “Animated GIF (*.GIF)” format.

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Lesson 10


XY Plots Use View, Select (F5) command to generate XY plots – also accessible from the Graphics Window’s context-sensitive menu. XY vs ID - plots XY data as a function of ID XY vs Set - plots XY data versus the output set number for an Output Vector across several Output Sets XY vs Set Value - similar to “vs Set”, except uses Output Set value for X XY vs Position - plots XY data vs the position of nodes or element in an axis direction for an output Vector in on Output Set XY vs Function - (not a post-processing option) plots XY data for a function

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Lesson 10


XY Plots of Functions Functions can be displayed quickly by selecting the function to be displayed in the Model Info window and selecting Show from the context-sensitive menu. • Opens a new graphics view titled “XY Show”

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Lesson 10


Freebody Display In the View Select dialog box, choose Deformed and Contour Data, Freebody Display Plots the Freebody information of the entire body or a select group of elements. •

Must have recovered Grid Point Force Balance data from analysis, if not only Applied and reaction forces will be available.

•

Total Summed Loads allows you to check the model for equilibrium.

•

Choose the types of entities to be viewed

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Lesson 10


Loads from a Free body Diagram Generate a Freebody diagram Select the Model, Loads, Loads from Freebody command Creates nodal loads from the free body diagram as displayed on the screen in the Active Load Set.

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Lesson 10


Vector Plots Multiple types of Vector plots can be generated using results data. •

Select Vector as the Contour Style in the View Select dialog box, then the Deformed and Contour button.

•

Once an Output Set is selected, click the Contour Vectors button to specify the options for the plot. This opens the Contour Options dialog box.

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Lesson 10


Contour Vector Options With the Contour Vector Options dialog box, you can set the: •

Vector Type •

Standard Vectors – tensors such as Total Displacement, Principal Stresses and Strains

•

Single Value, 2D and 3D Components – specify any of the output vectors

•

2D Tensor Plot (new in v10.1)

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10 - 16

Lesson 10


2D Tensor Plot Example Beginning with v10.1, you can generate a “Crows Foot” plot by setting the Vector Type to 2D Tensor Plot in the Contour Vector Options dialog box. •

Example : Display Laminate Ply 1 X and Y normal stresses and the Laminate Play page g for View Options p settings) g ): Failure Index of Plyy 1 ((see next p

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Lesson 10


2D Tensor Plot Preferences and View Options You can automatically set the View Options settings for a 2D Tensor Plot in Femap’s Preferences dialog box under the View tab by clicking the option for 2D Tensor Plot View Options Override.

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Lesson 10


Detailed Post Processing Options Accessed via the View, Options command (F6 and Ctrl+O hotkeys) •

Located in the Category, PostProcessing

Long list of options, key ones include •

Post Titles • On/off, Location…

•

Deformed Style • Scale, Automatic scaling options

•

Contour/Criteria Style

•

Contour Levels

•

Contour Legend

Note:

Post Processing options are saved along with the View Style in the View Library.

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10 - 19

Lesson 10


Post Toolbar Allows quick display of Deformed and Contour plots Detailed Postprocessing settings accessible from the Post Options pull down icon

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10 - 20

Lesson 11

Th Meshing The M hi Toolbox T lb

Purpose: The Meshing Toolbox is used for accessing FEMAP’s interactive geometry cleanup and idealization tools and interactive mesh editing tools. This lesson is an overview of the tools available in the Meshing Toolbox. Topics: 

Entity Locator



Feature Suppression



Feature Removal



Combined / Composite Curves



C bi d / B Combined Boundary d S Surfaces f



Mesh Sizing Toolbox



Mesh Locate Toolbox



Mesh Quality Toolbox

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Lesson 11

The Meshing Toolbox

Meshing Toolbox - Controls Similar to other FEMAP Panes, the Meshing Toolbox can be turned on and off from the Tools menu. The Meshing Toolbox has several controls for: •

Toolbox Visibility – toggle Meshing Toolbox controls

•

Toggle Entity Locator – toggle the feature Locator controls

•

Mesh Quality Toggle – toggle display of mesh quality

•

Automesh / Remesh Control – select either automatic remeshing or manual meshing after making an update in one of the Meshing Toolbox control controls

•

Select / Dialog Select icons – select a single entity or multiple entities using a Select dialog box

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Lesson 11

The Meshing Toolbox

Entity Locator for Curves The Locator makes it possible to quickly search for features in a model that could result in poor mesh quality. Locator controls are activated by toggling the Toggle Entity Locator icon. The Locator has an option to Search for: •

Curves

•

Surfaces

When Curves are selected the Search Method can be set to search for: •

Short Edges •

•

Based On •

Global Mesh Size

•

Curve Length

•

Shortest Curves

You can also select whether to locate the curve in the: •

Entire Model

•

Only in Group(s)

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Lesson 11

The Meshing Toolbox

Entity Locator for Surfaces When Surfaces are selected the Search Method can be set to search for: •

Small Surfaces •

•

Slivers •

•

Sliver Tolerance

Spikes •

•

Fit in Radius

Spike Width

By Area •

Area Less Than

You can also select whether to locate surfaces in the: •

Entire Model

•

Only in Group(s)

•

Not in Group(s)

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Lesson 11

The Meshing Toolbox

Entity Locator - Toggle Entity Locator Menu The Toggle Entity Locator icon is used to cycle through objects located through the Locator control. •

Remove deletes the current entity from the list of located entities

•

Do Not Locate deletes the current entity from the list of located entities and keeps the entity from being located again during the current model editing session.

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Lesson 11

The Meshing Toolbox

Feature Suppression Feature Suppression controls allow you to interactively suppress or remove suppression of: •

Loops – select one edge on an feature to automatically suppress the entire set of curves and surfaces comprising the feature

•

Curves – select curve(s) to be suppressed. Should not be used on solids.

•

Surfaces – select surface(s) to be suppressed Should not suppressed. be used on surfaces.

Limit Size prevents selection of entities that have their length less than the specified Smaller Than value. The Action Action menu toggles the action to : •

Toggle Suppression – if a entity is unsuppressed, suppress it. If it is suppressed, restore it.

•

Suppress or Restore

Update Colors set options to toggle and colors for suppressed entities entities. Show Suppressed allows you to highlight suppressed Curves or Surfaces Restore All features in either selected solid(s) (In Solids button) or in the entire Model

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Lesson 11

The Meshing Toolbox

Feature Removal Feature Removal differs from Feature Suppression in that the underlying solid or surface geometry is modified. •

Loops – includes an option to set the Limit Size for selecting loops.

•

Curves – includes an option to set the Limit Size for selecting loops loops. Also includes an option for Aggressive Removal

•

Surfaces - when a single surface on a solid is selected, Femap will attempt to clean up the solid to result in a “clean” solid. In some cases, no operation will be performed and in others, other adjacent surfaces will be removed. There is also an option for Aggressive Removal.

Note:

There is no option to restore removed features beyond what is supported with the Undo command.

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Lesson 11

The Meshing Toolbox

Combined / Composite Curves Combined / Composite Curves combines two or contiguous curves into a single curve for meshing. The can be created by: •

Add By Point – create th composite the it curve b by selecting a common point on the two curves

•

Add Curves

•

Split At – splits a composite curve at the selected l t d point i t



Remove – converts the composite curve at the selected position back to it’s the original curve definition. The remainder of the composite curve is retained.



Delete – converts all curves on the composite curve back to their original curve definitions

The Combine Surfaces option creates Combined Surfaces for surfaces using the curves that are combined.

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Lesson 11

The Meshing Toolbox

Combined / Boundary Surfaces Combined / Boundary Surfaces combines two or contiguous surfaces into a single surface for meshing. The can be created by: •

Add By Curve– create the composite surface by selecting a common edge on the g surfaces two original

•

Add Surfaces – converts the selected surface to a composite surface. If multiple surfaces are selected using the Dialog Select tool, the selected surfaces are combined into a single surface provided they are connected by a common edge.

•

Split Along– splits a composite surface by the selected curve(s)

•

Remove – converts the selected composite surface(s) their original surface definitions

•

Delete – converts the selected composite surface(s) to their original surface definitions

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Lesson 11

The Meshing Toolbox

Mesh Sizing Toolbox Mesh Sizing controls provides interactive modification of mesh sizes on curves. Set the mesh size on selected curve(s) with the Size Curves option. • Add – add the Number of Nodes to the current mesh size • Subtract – subtract the Number of Nodes from the current mesh size •

Set To – in this case, the number of elements on the curve will equal the Number of Nodes.

•

Specify the Spacing as either:

•

•

Equal

•

Biased – when this option ti is i enable, bl you specify the Bias Factor

Enable Length Based Sizing

When the Sizing Option is set to Match Curves, the curve(s) selected will match the mesh sizing settings of the Master Curve Enabling the Show Free Edges option highlights the nodes on the mesh’s free edges

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Lesson 11

The Meshing Toolbox

Mesh Locate Toolbox With the Mesh Locate controls, you can interactively move nodes to improve the quality of a mesh. •

Specify the attached mesh with the Select Mesh to Edit option: •

Attached To Surface

•

Attached To Solid

 Standalone Mesh – ignore attached geometry and modify the node locations freely  Locate Multiple - select multiple nodes and move them simultaneously The Locate Method specifies whether to move the node: • Dynamic – drag the position of the selected node(s) using the cursor p y the direction and distance to move the selected node(s) ( ) • Manual,, Vector – specify Smooth will move the adjust the other nodes of the attached elements to smooth the mesh quality Enabling the Project option constrains the node’s movement so that it remains attached to its surface Constrain to Curve constrains the node’s movement to remain attached to its curve Once a node or nodes have been moved, you have the option to Save or Discard the edit(s)

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Lesson 11

The Meshing Toolbox

Meshing g Toolbox – Mesh Quality Mesh Quality specifies the setting of the display when the Quality tool is enabled. •

•

Q Quality y Type yp specifies p whether to display the mesh quality by: •

Aspect Ratio

•

Taper

•

Alternate Taper

•

I t Internal l Angles A l

•

Warping

•

Nastran Warping

•

Jacobian

•

Combined Quality

Set the Number of Distortion Levels to: •

2 or 4

• Toggle Smooth Contours • Minimum Distortion displays the minimum element distortion value in the Meshing Toolbox pane • Max Distortion displays the maximum element distortion value in the Meshing Toolbox pane

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Lesson 12

Mid f i Midsurfacing

Purpose: Midsurfacing is a technique that is used to build idealized models of thin bodies. This lesson is an overview of the tools available Femap to create midsurface models. Topics: •

Midsurfacing

•

The Midsurface Commands

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Lesson 12

Midsurfacing

Midsurfacing Midsurfacing is the process of extracting the midplane between parallel surfaces in order to reduce the complexity and increase the accuracy of the Finite Element Model. •

For the part shown: •

Solids: 113,512 113 512 nodes and 63,875 63 875 elements. elements ( > 3 minutes solve time) time).

•

Shells: 1725 nodes and 1576 elements. (< 10 seconds solve time).

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Lesson 12

Midsurfacing

The Geometry, Midsurface Commands Geometry, Midsurface, Single in Solid •

Creates a single trimmed midsurface between two surfaces of a solid.

Geometry, Midsurface, Single •

Creates a single sheet surface between two surfaces that extends beyond the extent of b th surfaces. both f

Geometry, Midsurface, Trim to Solid •

Trims a surface with a solid and deletes any part(s) of the surface which lie outside the volume of the solid.

Geometry, Midsurface, Trim with Curve •

Trims or breaks a surface with a curve

Geometry, Midsurface, Extend •

Extends a surface by using one of a surface's edge curves and "extending“ the surface using a specified "Extend Shape“ method .

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Lesson 12

Midsurfacing

Geometry, Midsurface, Automatic Command Automatically generates the midplanes between the selected surfaces, trims them to the solid, and cleans up any surfaces that are determined not to be part of the model. •

Midsurfaces are extracted from parallel faces.

•

Automatically creates a group called “Midsurface” Midsurface

•

Use where the part has multiple wall thicknesses or has features that are “branching” or non-tangent.

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Lesson 12

Midsurfacing

Geometry, Midsurface, Offset Tangent Surfaces Command The Geometry, Midsurface, Offset Tangent Surfaces command is used to generate a Sheet solid from a constant thickness solid where the topology consists of continuous tangent surfaces. •

p y a surface on one of the surfaces to be midsurfaced. Femap p will Specify automatically select the chain of connected tangent surfaces.

•

Specify a Offset Distance. This is by default one-half of the solid’s thickness.

•

You have the option to delete the original solid automatically.

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Lesson 12

Midsurfacing

Geometry, Midsurface Commands (continued) The following three commands are the steps in order that the Geometry, Midsurface, Automatic command follows. •

Geometry, Midsurface, Generate •

•

Geometry, Midsurface, Intersect •

•

Creates midsurfaces Splits the selected surfaces at their intersections

Geometry, Midsurface, Cleanup •

Automatically determines which surfaces that can be deleted as a result of the Midsurface, Cleanup command. Does NOT delete the surfaces, but places them on a separate layer for inspection and user controlled deletion.

Geometry, Midsurface, Assign Meshing Attributes •

Prompt’s you for the material for the selected surface(s) and then automatically creates the properties with the wall thickness(es)of the original solid.

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Lesson 12

Midsurfacing

Using NonManifold Add for Midsurface Models Using Geometry, Surface, NonManifold Add on a midsurface model that is “ready for meshing” is often a great way to assure mesh continuity in the model, especially if “TJunctions” exist.

Original Solid Geometry

Midsurfaced Geometry 2 Sheet Solids and 2 curves at T-junction between Sheet Solids, both of which needs to be sized the same for mesh continuity

After NonManifold Add 1 “General Body” and 1 shared curve at T-junction allows for easier mesh sizing and assures mesh h continuity ti it

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Lesson 13

FEA Assembly A bl Modeling M d li

Purpose: In the context of FEA, modeling assemblies may use multiple techniques to connect the components of a FEA assembly. This lesson is an overview of the tools available in the Femap to model FEA assemblies. Topics: 

Finite Element Model Connection Types



Mesh, Connect Menu



Connecting FEA Components with Connectors



Bolted Connections with Bolt Regions



Fl id and Fluid dR Rotor t R Regions i

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The Lesson 12

FEA Assembly Modeling

Finite Element Model Connection Types Coincident Node Rigid Element Connections Welded Connections Mesh “Connections” and Properties Fluid and Rotor Regions

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The Lesson 12


Coincident Nodes Connecting Similar Element Types can be accomplished with “Coincident Nodes” •

Depending on how the model was set up before meshing (e.g. use of “Slice Match”, etc.), some meshes will be generated automatically with coincident nodes.

Use the Tools, Check, Coincident Nodes command. •

For large models, or models where you anticipate there a large number of coincident nodes, uncheck the List Coincident Entities option.

•

The Preview Coincident option is used to display coincident nodes before merging.

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The Lesson 12


Rigid Element Connections With most solvers, including NX Nastran, Shell and Beam Elements have 6 D.O.F. per node, while Solids Elements have 3 D.O.F. per node. •

Solid/Shell and Beam/Solid connections cannot be satisfied with use of coincident y nodes only.

•

If Solid/Shell, Solid/Beam, and Beam/Shell connections are not defined correctly, you will get a FATAL MESSAGE 9137 – SEKKRS (under-constrained model).

Rigid Elements can be used to transmit rotations between Solids and Shells and Solids and Beams by transferring the translation on the nodes on the plate elements to the nodes on the solid elements. •

Use a minimum of two “dependent” nodes on the solid for every independent node on the shell or beam.

Note:

Do not use mid-side nodes on parabolic elements as either Independent or Dependent nodes. nodes

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The Lesson 12


Rigid Elements Beginning with Femap v10.1.1, you can automatically generate the Independent node by selecting the option for New Node at Center. This option generates a new node by placing the node at the centroid of the Dependent nodes.

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The Lesson 12


RBE3 Rigid Elements Use the RBE3 Rigid Element to transmit masses, loads, and rigid body motion (velocity, acceleration). •

To create a RBE3, enable the Interpolation Factor in the Define RIGID ELEMENT g box,, then select the Nodes to Average. g dialog

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The Lesson 12


RBE3 Rigid Elements (continued) Resulting Rigid Element after selecting Nodes to Average.

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The Lesson 12


RBE3 Rigid Elements (continued) You can adjust the Interpolation factor for RBE3 elements using the following steps; 1) In the Define RIGID Element dialog box, select the node(s) for which you are

modifying the interpolation factor 2) Click the Update button 3) Modify the Factor in the Update Interpolation Element dialog box.

You can either change the value of the Factor, or you can select the Distance Weighting option that causes Femap to calculate a weighted interpolation factor based on that nodes distance from the Reference Node relative to all the other nodes selected in Step 1)

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The Lesson 12


“Converting” Rigid Element Types Once a RBE2 or RBE3 Rigid Element is created, you can Convert the element from a RBE2 to a RBE3 and vice versa.

Note how after selecting the Convert option, the interpolation factor for the nodes has been removed.

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The Lesson 12


Welded Connections Femap supports Weld Properties and Elements •

Creates CWELD elements for NX Nastran and MSC.Nastran only

•

Spot Weld uses an “effective length” calculation based on the thickness of the two shell elements connected connected.

•

Fastener allows direct input of stiffness matrix for weld properties

•

Multiple options for generating Weld Elements •

Note:

Orientation of Weld is defined by either “Projection” method or “Axis” method and may be limited by the type of Weld selected

Welded elements can only be created between plate elements.

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The Lesson 12


Mesh, Connect Menu Allows rapid generation of MPC’s, Rigid, and Line Element connections between meshes

Also allows “unzipping” of coincident nodes with option to automatically create connection types: •

None – leave nodes “unzipped”

•

Rigid Elements

•

DOF Spring Elements

•

Spring Elements (including CBUSH)

•

Gap Elements

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The Lesson 12


Connect Menu Connect, Automatic command finds the closest matching surfaces between solids and automatically generates “Connectors” (also known as “Contact Elements”) between adjacent “Connection Regions” •

p y search tolerance and type yp of contact Specify

•

Model Info window has a Connections object tree

Note:

For assemblies with existing slaved meshes or one that will be meshed with slaved meshes, placing a connection between the two parts at the location of the slaved mesh may result in a fatal NX Nastran error.

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The Lesson 12


Connection (Contact) Properties In the Define Connection Property dialog box, first select the tab for the solver used to solve a contact problem. For NX (Nastran) Linear Contact, the Contact Type pull down selects Linear or Glued contact. •

Glued contact can be used in ALL NX Nastran solutions.

•

Linear contact can be used only in NX Nastran Linear Statics solutions.

•

Always click the Defaults button when switching Contact Type or manually creating a new Connection Property.

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The Lesson 12


NX Linear Glued Contact Property Options Glued Contact has the following property options. In most cases, selecting the Defaults button will result in the proper settings.

•

Glue Type – specifies the glue formulation. formulation •

1..Spring – when this is selected, you can change the Normal Factor and Tangential (Penalty) Factors

•

2..Weld (default) – should be used for most cases as this prevents the introduction of artificial rotational energy into the connection. •

When selected, you can change the Glue Factor, but this is not recommended. d d

•

Eval Order - determines the number of "Linear Contact or Glue Points" for a single element on the source region.

•

Refine Source - determines if the source region is refined for the "Linear" or "Glued" Contact solution.

•

Penalty Factor Units - specifies how contact element stiffness is calculated.

•

Search Distance – if the two contact segments lie within this distance, NX Nastran activates glued contact between the pairs.

Note:

For more details on Glued Contact, see the NX Nastran User’s Guide, Section 9.7.

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The Lesson 12


NX Linear Linear Contact Property Options Linear Contact multiple. In most cases, selecting the Defaults button will result in the proper settings.

•

Friction – specifies the static coefficient of friction.

•

Min(imum) and Max(imum) Contact Search Distance – if the element faces of the contact segments are within these values, NX Nastran activates the linear contact algorithm for these contact faces.

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The Lesson 12


NX Linear Linear Contact Property Options (continued) •

•

Initial (Penetration) - Controls how NX Nastran handles initial gap or penetration of the generated contact elements.

•

0..Calculated (default) - Use the initial position of the nodes in the contact pairs. In the case of penetrations, a model may experience "press fit" behavior when using this option.

•

2..Calculated/Zero 2 C l l t d/Z P Penetration t ti - Same S as 0..Calculated, 0 C l l t d but b t if penetration t ti iis detected, set the initial contact force to zero (0).

•

3..Zero Gap/Penetration - Sets the penetration/gap to zero for all contact elements. Very useful when the contact surfaces are physically in contact, but due to mesh irregularities, penetration occurs.

Shell Offset – use the default (0..Include shell thickness) unless the contact segments t are defined d fi d att th the ttop off th the shell h ll mesh, h nott th the mid id plane l off th the shells. h ll

Note:

For more details on Linear Contact, see the Femap Commands manual, Section 4.4.3.1. You can also refer to the NX Nastran Users Guide, Chapter 19 for additional details on gluded and linear contact.

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The Lesson 12


Selection of Master and Slave Contact Segments When using either NX Nastran (Linear) Contact for NX Nastran Advanced Nonlinear Contact, the correct specification of which of the two contact segments used as the Source is important with respect to both the accuracy of the results and solution time. It is also critical when contact between two segments is unconstrained in shear contact except for friction. Femap uses the terms: •

Master to refer to the Target element face(s)

•

Slave to refer to the Source element face(s)

NX Nastran checks for contact between element faces from the Slave Slave’s s element faces to the Master’s element faces and internally builds contact element pairs between the two element faces. Therefore, as a rule, you should model with the following in mind:

Slave Mesh Density ≥ Master Mesh Density

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The Lesson 12


Modeling g Bolted Connections with Bolt Regions Model bolted connections with: •

Bar and/or Beam elements that comprise a Bolt Region

•

Bolt Preload – an axial force load applied to the bar or beam elements or Bolt Region

•

Two elements that connect the ends of the bolt to the rest of the mesh – usually Rigid elements

API script automates generation of bolt mesh – Custom Tools, Meshing, Hole to Hole Fastener •

Does NOT create the Bolt Region or the Bolt Preload

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The Lesson 12


Bolted Connection Example Two Aluminum Lugs with a Stainless Steel Pin •

Contact between lugs is modeled with Linear Contact

•

Pin is modeled as a two Beams with a 10 lb Preload – connected to lugs at ends with Rigid Element

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The Lesson 12


Fluid Connection Regions The Connect, Fluid Region command creates segments representing incompressible fluid volume regions used for the purpose of generating a virtual mass matrix (MFLUID entry in Nastran input files).

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The Lesson 12


Rotor Connection Regions Used to model Rotors for Rotor Dynamic analysis •

Use when more than one Rotor exists in a model and/or

•

A Rotor’s R t ’ axis i off revolution l ti is i nott coincident i id t with ith the th Global-Z Gl b l Z axis i

Valid only for SOL110 – Complex Modal Analysis (Normal Modes with Rotor Dynamics option) and SOL111 (Modal Frequency Analysis with Rotordynamics option)

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Lesson 14

Finite Modeling Debugging

Purpose: This lesson is an overview of methods to check and debug Finite Element Models. Topics: 

Finite Element Modeling Mesh Sizing



Results Checking



Model Debugging



Common Errors



Recommended Model Checks

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Lesson 14

FEA Modeling Debugging

Finite Element Mesh Sizing Depending on the desired accuracy of the model, a course mesh (low number of larger elements) or a fine mesh (high number of smaller elements) must be created. For instance, a more complicated structure requires a finer mesh in order to produce accurate answers.

Pros

Lower number of Elements Coarse Model

Fine Model

femap101-g-v10.1.1

Less Degrees of Freedom

Cons

Less accuracy for complicated geometry t

Reduced Solve Time

Distorted elements can be too stiff and misrepresent response

Accuracy for complicated geometry is improved

Higher number of Elements

Less distorted elements improves results

Increased Solve Time

More Degrees of Freedom


14 - 2

Lesson 14


Checking Results It is always a good idea to do a “reality check” with the results of any Finite Element Analysis. Using engineering knowledge and common sense will allow a user to determine if the results make sense for the applied boundary conditions. For instance, an under-constrained or “unconnected” (nodes not merged where they should be) model may exhibit much larger displacements than expected a displacement in the opposite direction of the applied load during a linear cantilever beam analysis. Some Good Practices: •

Always visually plot the models elements if possible for verification

•

Make sure responses correspond with applied boundary conditions

•

Check input loads with reaction forces: ΣF = 0

•

Hand calculations are always a great idea whenever possible

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Lesson 14


Model Debugging Recommended minimum checks on input •

Stiffness matrix checks •

At the G-size

•

Aft MPC P After Processing i

•

After All Processing

Mass Checks •

Grid point weight generator output

•

Rigid-body mass checks

•

Assembly mass checks

Loading checks

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Lesson 14


Model Debugging (continued) Structural plots are useful primarily to visually verify model geometry. Other tools must be used to assess the numerical accuracy of a finite element model. These tools include many automatic error checks performed by NX Nastran and user-supplied diagnostic requests in the form of DIAG, PARAM, DMAP Alters, and Case Control requests. NX Nastran performs many error checks during an analysis to ensure that all input data is in the proper format and usable. If an error is detected during data processing, an error message is generated. If the error is fatal, the analysis terminates. Many times NX Nastran errors have a number and a short description of the error which shows up in the .f06 file. Many times the same error number can represent a variety of different issues. In cases where the error is not obvious, consult the Help->Analysis menu and choose the error message segment where the Error Message number appears. Go to the error number for a broader description.

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Lesson 14


Model Debugging (continued) Perform independent hand checks to verify the accuracy of the results Other potential pitfalls for new users include: •

First time use of a new capability. It is always a great idea to make a small test model in order to see how NX Nastran functionality works as it will take less time to debug and give insight into the usage of the feature •

Reference the Femap Examples document as this has examples of nearly all types of analyses that can be performed with Femap and NX Nastran.

•

Refer to NX Nastran documentation as these document details on many advanced solutions . Some of the documents included with Femap are: •

Basic Dynamic Analysis User’s Guide

•

Advanced Dynamic Analysis User’s Guide

•

Design Sensitivity and Optimization User’s Guide

•

Basic Nonlinear Analysis Users’ Guide

•

Advanced Nonlinear Theory and Modeling Guide

•

Thermal Analysis User’s Guide

•

Use of consistent units is of utmost importance!!!

•

Always use unique IDs – NX Nastran sometimes allows for duplicate element IDs, but not always. Duplicates can and do lead to problems, especially during data recovery

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Lesson 14


Common Types of Errors Mistakes in engineering judgment Approximations to physical behavior Engineering Theory Finite Element Theory Finite Element Implementation Modeling • Bolted connection • Welded connection • Corners • Transitions Connections • Beam to Plate • Beam to solid • Plate to solid

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Lesson 14


Common Types of Errors (continued) Beam Orientation Beam Releases Loading (Make sure that the model is loaded accurately) Finite Element Error Round-off Error (Can cause serious, serious problems) •

Computers use binary arithmetic (user enters 0.1, internally it may be 0.099999999998)

Program Bugs (Please Report them to UGS Solutions via GTAC) •

A list of known errors is maintained and distributed

Plates not lining up (zipper effect)

Any connections depending on in-plane rotational stiffness of plates, or any rotational stiffness on solids Instabilities – example: releasing both ends of a beam in torsion Offsets of elements in wrong coordinate system (should be in the output coordinate systems of the grid points for Bars and Beams) Member Properties wrong (Beam orientation) or in plates Membrane only (left out bending) Beam end releases – local or global (in beam coordinates)? Element force output is normally in element coordinate system

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Lesson 14


Minimum Recommended Model Checks Pre-Analysis Understand the structure and the elements •

Make Small Models in order to understand the problem

•

Make pilot models in areas of uncertainty

•

If unfamiliar with an element type that needs to be used, make simple models and compare the answers to theory

Model checks before analysis •

Geometry

•

Undeformed plots

•

Look at connections between different element types

•

Based on knowledge of elements

•

Based on Loads

•

Look at corners (QUAD plates)

•

Shrink plots

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Lesson 14


Recommended Model Checks - Elements Beam and bar • Check that both ends of the beam have correct orientation (I1 and I2) • Check end releases (in element coordinates) p coordinate system y of GRIDs)) • Offsets ((in output Plates and Shells • Check aspect ratios, taper, and warpage • Check orientation (element normals), surfaces consistent • Check attachments (in-plane rotational stiffness, corners, etc) • Offsets (in element coordinate system) • Material need E E, ν (or G) G), and ρ • Property entry – be sure to get the correct properties (One of the most common errors is not specifying MID2 for “bending” plates) Solids • Check aspect ratios • Check taper • Check attachments (Any attachments depending on rotational stiffness stiffness, require a special modeling effort) • Material need E, ν (or G), and ρ

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Lesson 14


Recommended Model Checks Mass properties •

Check ρ on MATx entries

•

Check NSM on property entries

•

B Bars, b beams = mass/unit / it length l th

•

Plates = mass/unit area

•

Submit with PARAM, GRDPNT,xxxx where xxxx = ID of GRID point to calculate mass properties about

•

Check center of gravity and total weight (mass) versus known values

L d Loads •

Verify they are correct (OLOAD RESULTANT)

•

Run the Femap command, Tools, Check, Sum Forces

Constraints •

Verify that they exist (often forgotten and overlooked)

•

Verify they are correct (location and orientation – in output coordinate system of the GRID points)

•

Verify they are applied (SPC CASE CONTROL command)

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Lesson 14


Recommended Model Checks - Continued Static Checks •

Apply 1-G in X,Y, and Z directions independently

•

Check load paths (GPFORCE)

•

Ch k Reactions Check R ti (SPCFORCE)

•

Does total = applied load?

•

Are the reactions at the correct locations and do they have the correct orientation?

Equilibrium check – verify model is not over-constrained •

Run free-free normal modes analysis.

•

Remove known constraints and check for unconstrained motion under applied loads or imposed displacements

Thermal equilibrium check (if Thermal loads are being considered) •

Check α on MATx entries

•

Check for unconstrained set of constraints

•

Apply a determinate set of constraints

•

Use the same α for all materials

•

Apply a uniform ∆T to the structure. It should expand “freely”, meaning that it will create no reactions, element forces, or stresses

Statics •

•

Check EPSILON and MAXRATIO •

EPSILON > 10-9 may indicate trouble

•

MAXRATIO > 105 may indicate trouble

Check reactions •

Do theyy equal the applied loads?

•

Check load paths – use grid point force balance to “trace” loads

•

Check stress contours for “consistency”

•

•

“Sharp” corners indicate bad modeling

•

Use different options (i.e., topological and geometric) and compare results

Compare values to “hand calc” or small model results

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Lesson 14


Recommended Model Checks - Dynamics Dynamics – normal modes •

Check frequencies. Are they in the expected range?

•

If free-free, are there six “rigid-body” (f = 0.0) modes?

•

A there Are th any mechanisms h i (f = 0 0.0)? 0)?

•

More than six “rigid-body” modes in free-free?

•

Any “rigid-body” modes in constrained modes?

•

Check Mode Shapes. Identify Modes.

•

Plots

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Appendix A p Preferences Femap

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Appendix A

Femap Preferences

Femap Preferences Preferences are used to configure Femap for optimum performance and the way you prefer to work •

Preferences are stored in the femap.ini file under the main Femap installation folder

•

If you specify a different Start In location for your Femap startup shortcut shortcut, Femap will first look in that location for a femap.ini file and use the preferences set in that file. In addition, any changes to preferences will automatically be stored in the femap.ini file in that folder.

Set preferences with the File, Preferences command •

Messages – set font and fonts sizes

•

Views

•

Render

•

User Interface

•

Database – set performance options

•

Geometry/Model

•

Interfaces – select default Analysis Interface

•

Library/Startup

•

Color

•

Spaceball

Many Femap preferences will take effect immediately after theyy have been set, but in some cases you will need to close and re-open Femap for the changes to take effect. Examples are: •

Advanced/Debug Options for Render graphics

•

Database

•

Fonts changed in the Messages Window, etc.

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Appendix A

Femap Preferences

Femap Preferences – Messages and Views The Messages tab (see previous page for snapshot of dialog box) sets the fonts and colors displayed in the Messages window. The Views tab allows you to: •

Specify a Startup View (from the View Library) used when creating a new Femap model.

•

Specify the Background Bitmap or Logo for Render Views.

•

Set Picture Copy and Picture Save Defaults

•

Set view options such as turning the Workplane automatically off in new views

•

Alternate Contour Palette sets Blue as the lowest color for the lowest color in post postprocessing displays vs. the normal Magenta.

•

Specify View and Dynamic Rotation options. •

Try changing the Dynamic Speed option if flickering is encountered during dynamic rotation.

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Appendix A

Femap Preferences

Femap Preferences – Render Render mode is a high-speed graphics mode that uses the OpenGL graphics language. The Render dialog box lets you control the level of functionality that you have while in Render mode. •

Hardware Acceleration can be toggled off if the graphics card, or it's drivers, are causing instability in Femap.\

•

Including less entities with the Include In Dynamic Rotation option will speed up dynamic rotation of large models.

•

Advanced/Debug messages can be turned on to help the Development team diagnose complex geometry issues if they arise. •

Setting the BitBlt Delay can be used to help with performance on consumer or game-oriented graphics cards.

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Appendix A

Femap Preferences

Graphics Card Performance Considerations Desktop area resolution should be taken into consideration when using Femap. Having a very fine screen resolution can increase the time animations need to generate and the time individual windows need to refresh. If Femap appears to be having graphics errors errors, it could be the driver for your graphics card. Update the drivers for your graphics card often! •

Drivers from the manufacturers of the graphics card chipset tend to be more stable then the drivers from the maker of the graphics card. (e.g. use an ATI or nVidia driver vs. an ASUS driver)

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Appendix A

Femap Preferences

Femap Preferences – User Interface Menus and Dialog Boxes sets preferences for Alternate Color Schemes, Autorepeat Create Commands, and the number of Recently Used Files Remember Dialog Positions tells Femap to remember where a user has placed a specific ifi dialog di l box b on the th screen (during (d i the th currentt F Femap session). i ) Graphical Selection options can be used to set the Tooltip Delay and Tooltip Duration Times for Tooltips Dockable Panes can be set to animate the “fly-out” from the docked and tabbed positions or simply pop-up. Show Entities Defaults settings are used to set default options for using the Show When Selected in the Model Info pane, Data Table, or the Preview button in an Entity Selection dialog box. Set Toolbars options to save and load layouts of toolbars and dockable pane(s)

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Appendix A

Femap Preferences

Femap Preferences – Database Defines various performance settings •

Preserve Next ID during Rebuild will cause Femap to not “backfill” empty entity IDs with new entities after using the File, Rebuild command.

•

Set Blocks/Page and Max Cached Label for improved RAM management and performance.

•

Sets the amount of memory used for Femap •

•

Short vertical line in color bar indicates memory used in the current model.

Installed RAM (Mb)

Blocks/Page

64

1

128

2

256

3

Open/Save Method •

512 5 This option should only be used f you are experiencing VERY 1000 11 slow opening/saving FEMAP| model files. On certain hardware, switching to option “2..64K widows I/O” may make a dramatic difference in the time a model takes to open/save.

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Appendix A

Femap Preferences

Femap Preferences – Database (continued) Specify Scratch Directory for the location of the temp, scratch, and recovery files Femap writes out. •

Without a TEMP variable, the location of the Femap scratch files defaults to your g Settings\Temp g p folder. In manyy cases,, Documents and Settings\USERNAME\Local this is a location on the network other than your local PC.

Note: Setting the Femap Scratch folder or setting the TEMP variable to a network file location may seriously degrade Femap’s performance and dramatically increase file save times. In addition, if your network fails for any reason, any opened p files in a Femap p session have the p potential to be corrupted. p

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Appendix A

Femap Preferences

Femap Preferences – Geometry/Model Select between the Parasolid or Standard geometry engines to start with. The Parasolid engine is recommended. Femap stores geometry in meters. The Solid Geometry Scale Factor is used to i t internally ll store t your geometry t units it as meters t in i P Parasolid. lid •

For example, if you select Inches, the Scale Factor is 39.37 (inches/meter). Femap uses the inverse of this number to store the geometry in its model database (1 inch = .0254 meters).

•

This scaling will allow you to import and model parts that are outside of the Parasolid modeling limits ( +/-500 x 500 x 500). Note: If you import geometry with a different scale other than the file’s original scale, new or modified geometry will be out of scale with the imported geometry.

FEMAP can be set to Delete Construction Geometry, Move it to the “NoPick Layer”, or simply do nothing when used. Element Quality checks can be turned on or off permanently and default values set for each quality check via the Element Distortion button. Default output orientations for various element shapes can be permanently set for use when transforming results from the Output Orientation button. The Alternate Section Property Calculator can be turned on in this dialog box. By choosing this option, option values generated by the Femap beam section property calculator will be attained using an alternate method which in certain cases will be more accurate than the standard method. Pre-V10 Tet Meshing and Surface Meshing can be set as the defaults. This will allow FEMAP 10 to use the “older” meshers instead of the “new” meshers, should any issues arise.

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Appendix A

Femap Preferences

Femap Preferences – Geometry/Model (continued) Load Expansion on Midside Nodes sets the defaults for modification of the distribution of Geometry-based loads (such as Forces on Surfaces and Moments on Curves) when these loads are expanded to the nodes on Parabolic elements at the time of analysis. To obtain an even distribution of force across a parabolic element, most programs require a larger portion of the force be assigned to the midside nodes. •

You can set the factors Along Edges, On Tri-Face, or On Quad-Face to represent the amount of the total load on the element which will be applied to the midside node.

•

You will typically want to use the default values as shown above, as well as use the Midside Node Adjustment Default. If you have further questions on the distribution required for your solver program, please consult the reference documentation for your analysis program.

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Appendix A

Femap Preferences

Femap Preferences – Interfaces Interfaces sets the default analysis interface. The defaults can be defined for each interface (e.g. NASTRAN, ABAQUS, etc.) •

The Enable Old Analysis Interfaces option allows the import of models and results pp solvers. from older,, unsupported

Setting the File Reference Options allows FEMAP to check if imported Geometry, Analysis Input decks, and/or Analysis Results have been modified when a FEMAP model is opened. Use the File, References command to check references during a FEMAP session. Increase the value of Max Lines to Monitor from the default value of 5000 if you like to view the .f06 file during analysis execution.

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Appendix A

Femap Preferences

Femap p Preferences – Library/Startup, and Colors The Library preferences allow you to specify default FEMAP library files. •

Objects saved such as Materials, Functions, etc. are saved into the preferred library.

The Colors preferences allow you to select the default colors for entities. The Spaceball preferences allow you to specify certain parameters to improve the performance and overall behavior of Spaceball devices with regard to FEMAP.

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FEMAP Student Guide

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