1. Chapter Two
Simulation Basics

2. Chapter Overview
In this chapter, the basics of using Simulation to perform analyses will be covered, which include:
The Simulation GUI and Operation
Introduction to the Simulation Wizard
Basic Analysis Procedure
The capabilities described in this section are generally applicable to the ANSYS DesignSpace Entra licenses and above, unless explicitly noted with the lower-left hand table.
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3. A. Launching Simulation
Recall that there are two ways of running Simulation:
Configured from within ANSYS Workbench …
… or directly from a supported CAD system
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Model shown is from a sample Solid Edge assembly.

4. … Simulation Interface
The components of the user interface are shown below:
Short descriptions of each component are covered next
Tree Outline
Details View
Graphics Window
Toolbars
Simulation Wizard
Menus
Workbench Tabs
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5. … GUI – Menus
The menus provide much of the functionality present in Simulation. Covering each menu item may be tedious, so only the more commonly used menu items are covered below:
The titlebar lists the currently active ANSYS license
“File > Save” to save the .dsdb Simulation database
“File > Clean” to delete mesh and/or results from database
“Edit > Select All” to select all current entities in the window
“Units” to change units on-the-fly
“Tools > Options… ” to customize settings and options
“Help > ANSYS Simulation Help” to invoke documentation
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6. … GUI – Toolbars
There are four sets of toolbars to provide users quick access to functionality also found in the menus.
The toolbars can be repositioned anywhere on the top of the Simulation window
The “Context” toolbar, as will be illustrated later, will change, depending on what branch is active in the “Outline” tree.
Tooltips appear if the cursor is placed over the toolbar button
A “Unit Conversion” toolbar is also available (not shown)
Standard Toolbar
Graphics Toolbar
Named Selection Toolbar
Context Toolbar
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7. … GUI – Toolbars The “Standard” toolbar is shown below:
The “Graphics” toolbar is used very often:
The left mouse button can be either in “selection” mode or “graphics manipulation” mode. The above toolbar buttons grouped as “select entities” and “graphics manipulation” control the left-mouse button behavior.
The selection of entities of the CAD geometry can be done either by individual selection or by box-selection. This is controlled by the “Select Mode” icon
Save .dsdb
Bring up Simulation Wizard
Solve Model
New or Open .dsdb
Capture Snapshot
Graphics Manipulation
Select entities
Select Adjacent
Wireframe
Fit All
Select mode
Viewports
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8. … GUI – Outline Tree
The Outline Tree provides an easy way of organizing the model, materials, mesh, loads, and results for the analysis
The Outline Tree is analogous to the “tree” found in many CAD software. However, instead of sketches and features, this tree contains analysis-related items
The “Model” branch contains the input data required for the analysis whereas the “Engineering Data” branch holds generic material and convection data
The four main sections of the “Model” branch include “Geometry,” “Contact” (if present), “Mesh,” and “Environment.”
The “Environment” branch contains the loads as well as the “Solution” branch, which holds results for postprocessing.
Other branches (not covered here) are also available.
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9. … GUI – Outline Tree
The Outline Tree shows icons for each branch, along with a status symbol. Examples of the status symbols are below:
Checkmark indicates branch is fully defined/OK
Question mark indicates item has incomplete data (need input)
Lightning bolt indicates solving is required
Exclamation mark means problem exists1
“X” means that item is suppressed (will not be solved)
Transparent checkmark means body or part is hidden
Green lightning bolt indicates item is currently being evaluated
Minus sign means that mapped face meshing failed
1 Example is opening a Simulation database which contains a capability not available with the current ANSYS license used.
The user should become familiar with the basic status symbols shown here, so he/she can easily determine if the model is OK.
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10. … GUI – Details View
The Details View provides a means of inputting data. The contents will change, depending on branch selected.
White field: shows current input data
Data in white text field can easily be changed by clicking on it, then entering data, as needed
Some white fields require the user to select geometric entities on the screen, then click on “Apply”. Others require text data input from keyboard or selecting item from pull-down menu.
Gray (or Red) field: shows informative data
Data in gray fields cannot be modified. These fields usually provide information or results data, such as the maximum stress or number of nodes generated by the mesher.
Yellow field: incomplete input data
Data in yellow fields indicate that not enough information has been supplied. Users need to fill in data completely in order to solve model.
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11. … GUI – Graphics Window
The Graphics Window shows the geometry and results. It can also provide worksheet (tabular) listings, the HTML report, and a Print Preview option.
The Job Status tab provides information on jobs being solved remotely.
The remote solve capability will be discussed in the Simulation Advanced Training Course
Geometry Tab
Worksheet Tab
Job Status Tab
Print Preview Tab
Report Preview Tab
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12. … GUI – Simulation Wizard
The Simulation Wizard is an optional component, a useful aid to remind users steps required to complete an analysis
The Simulation Wizard provides a list of required steps and the status of them
Green checkmark indicates the item is complete
Green “i” shows an item to verify
A greyed symbol shows that the item cannot be performed yet until the previous step is completed
A red question mark means that there is an incomplete branch related to this item, analogous to the “?” status symbol on the Outline Tree
An “x” means that the item is not performed yet
A lightning bolt means that the item is ready to be solved by selecting on the Standard Toolbar
The Simulation Wizard can be toggled on/off by selecting the button on the Standard Toolbar
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13. B. Startup Panel
When first attaching a model to Simulation, the Startup Panel is shown, allowing the user to select a Simulation Template
This startup panel can be turned off in “Tools > Options … > Simulation: Startup”
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14. … Startup Panel
The benefit of the Startup Panel is that the appropriate results and Simulation Wizard will appear
Templates and Wizards are only available for analyses supported in DesignSpace licenses
“Stress Branch” is selected in the example below. Note that results and the Stress Wizard are automatically chosen
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15. … Simulation Wizard
By selecting an item on the “Required Steps” checklist, a callout appears, illustrating how that function is performed.
In the example below, “Verify Materials” was selected, and the callout shows the user where this item can be changed.
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16. … Simulation Wizard
The Simulation Wizard is very useful to analysts or other engineers who do not use Simulation every day
Reduces learning curve, as callouts show user where the item is in GUI
Besides basic functionality, callouts for more advanced items are also available as shown on right
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17. C. Basic Procedure
The purpose of simulation is usually to determine the response of the system based on some type of excitation or loading.
It is crucial to remember that a mathematical model is used:
CAD geometry is an idealization of the physical model
The mesh is a mathematical representation of the CAD model
The accuracy of answers is determined by various factors:
How well the physical model is represented depends on the assumptions
Numerical accuracy is determined by the mesh density
CAD Model
Finite Element Mesh
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18. … Basic Procedure Every analysis involves four main steps:
Preliminary Decisions
What type of analysis: Static, modal, etc.?
What to model: Part or Assembly?
Which elements: Surface or Solid Bodies?
Preprocessing
Attach the model geometry
Define and assign material properties to parts
Mesh the geometry
Apply loads and supports
Request results
Solve the Model
Postprocessing
Review results
Check the validity of the solution
Preprocessing
Solution
Postprocessing
Preliminary
Decisions
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19. … Basic Procedure
A sample analysis using the Stress Wizard will be shown in this section.
The Wizards in Simulation aid the user in following the basic analysis template discussed previously, and these steps below will be covered in the next slides:
Attach/import geometry
Assign material properties
(Mesh geometry)
A default mesh will be supplied by Simulation if this step is not performed manually by the user
Apply loads and supports
Request results
Solve model
Review results/postprocessing
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20. … Attach Geometry
Earlier, it was shown that geometry can be attached to Simulation in two ways
Direct from CAD system
For supported CAD packages only using plug-in mode
From within a blank Simulation session
For all supported formats, using plug-in or reader mode
Attaches active CAD model (plug-in mode)
Browse for CAD file (reader mode)
Directly launches Simulation and attaches geometry (plug-in mode)
Method 1
Method 2
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21. … Assign Material Properties
After importing a model, the Stress Branch template was chosen, and the Stress Wizard appears
“Verify Materials” is selected, and the callout shows how to change material properties in the pull-down menu
After “Verify Materials” is selected, all of the parts from the “Geometry” branch are highlighted, and the Details view shows how to change the material.
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22. … Assign Material Properties
Notice that the Details View allows the user to select a material from a pull-down menu
The default material property is “Structural Steel” but can be changed
By selecting “Import …” the user can select a material property file (XML format)
Although a few material properties are supplied with Simulation, as with any other input data, the user should use his/her own material data values.
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23. … Assign Material Properties
Materials may be individually selected for each part
Note that the part name is obtained from the CAD model
Multiple instances of the same part are differentiated by number
Multiple parts can be highlighted and changed at once
Use Shift-Left mouse button to highlight all items in range
Use Ctrl-Left mouse button to individually add/remove selection
By using a combination of Shift-Left mouse button and Ctrl-Left mouse button, twelve parts are highlighted on the Outline Tree
The user can then change all materials at once in the Details View by selecting the material pull-down menu.
Note that DesignSpace Entra is limited to analysis of single parts.
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24. … Assign Material Properties
Material properties are listed, modified, imported or exported by accessing the “Data” tab
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25. … Assign Material Properties
Default settings for material properties can be changed in the “Tools menu > Options… > Simulation: Engineering Data”
The default material can be changed from “Structural Steel”
Items to be always available in drop-down menu can be added
New materials can be added from various locations
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26. … Insert Loads & Supports
After verifying and assigning materials, the “Insert Loads” item is selected from the Stress Wizard
Structural (and thermal) loads are applied from the pull-down icon in the Context toolbar.
After “Insert Loads” is selected, notice that the “Environment” branch is highlighted.
By highlighting the “Environment” branch, the Context toolbar and Details view change.
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27. … Insert Loads & Supports
Loads and supports are applied on geometric entities
There are two ways to accomplish this:
Select geometry entity in Graphics Window first, then select load or support from Context Toolbar
Select load or support from Context Toolbar first, select geometry entities in Graphics Window, then click on “Apply” in Details View.
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28. … Insert Loads & Supports
After assigning the load on geometric entities, the user can enter additional data in the Details view, if necessary.
Notice that, in the Outline Tree, the associated load branch symbol status will also change to ‘completed’ (checkmark)
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29. … Insert Loads & Supports
For some structural loads, direction is often needed:
Selection is done in Details View of load
If “Components” is chosen, enter X, Y, or Z Components of loading
If “Vector” is chosen, select geometry and enter magnitude of loading
Defaults can be set in “Tools > Options … > Simulation: Miscellaneous > Load Orientation Type”
The World Coordinate System can be referenced
Direction is shown with triad in Graphics Window
World Coordinate System orientation and origin from CAD system
For this situation, use “Define By: Components” in “Details” view. Then enter x, y, and/or z components for load
(User-Defined Cartesian Coordinate Systems may also be used, as will be discussed later)
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30. … Insert Loads & Supports
On the other hand, existing geometry can be referenced:
In the “Details” view, select “Define By: Vector” to use existing geometry for vector orientation
Three types of existing geometry can be used
Normal to planar face or along axis of cylindrical face
Along straight edge or normal to cylindrical edge
Two vertices defining vector
Click on “Direction” and select geometry used for vector orientation. If vector is pointing in opposite direction, use the arrows in the Graphics window to toggle the direction. Click on “Apply” when done.
Enter magnitude for loading in “Magnitude.”
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31. … Mouse Controls
At this point, it will be useful to review mouse controls in the Graphics Window:
The left mouse button is used to select geometric entities OR to manipulate the graphics display
Left mouse button behavior is controlled by Graphics Toolbar
User can select items (vertex, edge, surface, body) or manipulate the view (rotate, pan, zoom in/out, box zoom)
Select mode can be single-select or box-select
In single-select mode, click-drag with left mouse button to “paint select” multiple items
Use Ctrl-Left mouse button in single-select mode to select or unselect multiple entities
In box-select mode, click-drag from left to right selects entities fully enclosed in bounding box
In box-select mode, click-drag from right to left selects any entity partially enclosed in bounding box
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32. … Mouse Controls In select mode, the middle mouse button changes view
Click-drag middle mouse button to dynamically rotate model
Shift-Middle mouse button pans model
If present, the wheel can be used to zoom in/out
(This way, user does not always have to toggle left mouse button between select mode and graphics manipulation mode)
The right mouse button provides context-sensitive pop-up menu if clicked once in Graphics Window
Click-drag right mouse button to box zoom in area of interest
Click right mouse button once and select “Fit” to fit model in view
Single-click right mouse button provides context-sensitive pop-up menu
Click-drag right mouse button allows user to box-zoom in region
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33. … Applying Loads and Supports
By taking advantage of the mouse controls, it can be relatively easy to apply a load (or support) to multiple faces
In example below, user can use Ctrl-left mouse button to single-select surfaces (highlighted in green)
Use of middle mouse button allows user to rotate model to more easily select certain surfaces in ‘back’ of model
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34. … Insert Results
By selecting the Stress Branch template in the beginning, some results are already requested. However, the user can request other results, if needed.
By selecting “Insert Results” in the Stress Wizard, the callout shows how to add results
Note that the “Solution” branch is now highlighted.
Because the “Solution” branch is selected, the Context toolbar and Details view changes.
Results, such as stress, strain, and deformation can be requested from the pull-down icons on the Context toolbar. New result items will then appear under the “Solution” branch.
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35. … Solving the Model
After verifying materials, applying loads and supports, and inserting results, the model is ready to be solved.
Selection of “Solve” in the Stress Wizard produces a callout showing the user that the lightning bolt icon is used to initiate a solution
Starting the solution will include automatically meshing the model if it has not been done so previously.
The solution may take a few minutes to a few hours, depending on how large the model is and the hardware used. A progress bar will be shown to indicate roughly how long the solution will take. The solution can also be stopped via the progress bar.
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36. … Solving the Model (ANSYS Details)
For regular ANSYS users, it may be useful to note that the solution is performed in batch mode.
An ANSYS input file is generated, and the details of the Output File can be viewed if a “Solution Information” result branch has been requested under the “Solution” branch
In Worksheet view of the “Solution Information” branch, the contents of the Output File will be updated with a frequency as specified in the Details view.
The location of the input file “ds.dat,” output file “solve.out,” and scratch files are located in the system TEMP directory by default.
This solver directory can be changed under “Tools > Options… > Simulation: Solution > Solver Working Directory”
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37. … View Results
After the solution is complete, the user can View Results
The type of results is dependent on the analysis performed
Contour, vector plots, and animations can be viewed
To view results, as the callout shows, the appropriate branch needs to be selected.
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38. … View Report
In preparation for generating the HTML report, one can add figures and comments from the Standard Toolbar
Select a branch first, such as “Equivalent Stress”
Then select the appropriate Standard Toolbar button:
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39. … View Report
After adding any figures or comments, select “View Report”
Preliminary information can be entered, such as author name
Select “Generate Report” to create HTML report
The HTML Report can be selected under the “Solution” branch via “Report Preview” tab, as the callout indicates.
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40. … View Report The HTML report will be displayed in Simulation
Comments and figures added will appear in the report
The HTML report generator includes all input and results associated with the simulation, providing complete documentation of the analysis.
This provides time-saving yet customizable report that can easily be generated by the user.
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41. … View Report
Reports are always dynamically generated, so the user needs to save the report, otherwise it will be overwritten
The report can be “published” as HTML files in a different directory or an internal web server, ed, or sent to Microsoft Word or PowerPoint
The Appendix at the end of the HTML Report will show the location of the various files used to created the report.
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42. D. Workshop 2 Workshop 2 – Simulation Basics Goal:
Using the Stress Wizard, set up and solve a structural model for stress, deflection and safety factor.
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