Chapter Nine CAD Parameters CAD Parameters Chapter Overview

Chapter Nine CAD & Parameters

CAD & Parameters Chapter Overview Training Manual • The following will be covered: – CAD Interoperability – Multiple Design Studies – Parameter Manager • The capabilities described in this section are generally applicable to all ANSYS licenses. However, some CAD functionality are specific to certain CAD software, so these will be designated accordingly. ANSYS Workbench – Simulation • In this chapter, interoperability with CAD software as well as parameters will be discussed. – Not all CAD software have the same features, so there are some differences in CAD-related functionality which is supported in Simulation March 29, 2005 Inventory #002215 9 -2

CAD & Parameters A. CAD Interoperability Training Manual – The Geometry Interface license can be run in reader mode for all licenses. The Geometry Interface can be run in plug-in mode for the CAD software listed under “Associative” • Detailed CAD support listing in Simulation online help • IGES Geometry Interface reader is free ANSYS Workbench – Simulation • As noted in Chapter 1, the following Geometry Interfaces are supported in Simulation: March 29, 2005 Inventory #002215 9 -3

CAD & Parameters … Design. Modeler & CAD Training Manual Design. Modeler has a similar look and feel to Simulation Design. Modeler can be used to create geometry in lieu of other CAD software Design. Modeler can also read in parts and assemblies from the same CAD sources as Simulation. These models can be prepared and modified for analysis, then attached in Simulation ANSYS Workbench – Simulation • Design. Modeler is a Workbench module allowing users to create or prepare models for use in Simulation March 29, 2005 Inventory #002215 9 -4

CAD & Parameters … CAD Interoperability Training Manual ANSYS Workbench – Simulation • There are various items which can be brought in from supported CAD systems when models are attached: – Geometry import – Spot weld import – Parameter import – Material property import – Coordinate system import – Named selection import – Motion loads import – CAD attribute processing • There are three ways of setting import preferences when attaching CAD geometry. – Three methods – one through the Workbench Projects page, another in Simulation Geometry branch, the third in Options… box – will be discussed next. March 29, 2005 Inventory #002215 9 -5

CAD & Parameters … Controlling CAD Settings Training Manual – These settings only affect the existing model ANSYS Workbench – Simulation – When importing models in Workbench Project page, the left side controls various CAD-related settings March 29, 2005 Inventory #002215 9 -6

CAD & Parameters … Controlling CAD Settings Training Manual – These settings only affect the existing model Model shown is from a sample Inventor assembly. ANSYS Workbench – Simulation – On the other hand, after a model is already imported into Simulation, CAD-related settings can be changed under the Geometry branch March 29, 2005 Inventory #002215 9 -7

CAD & Parameters … Controlling CAD Settings Training Manual – “Options” dialog box also accessible from Workbench Start page in lower-left corner. ANSYS Workbench – Simulation • To change default behavior, go to “Tools menu > Common Settings: Geometry Import” to change default behavior March 29, 2005 Inventory #002215 9 -8

CAD & Parameters … Geometry Import Training Manual – One cannot import a part with mixed solids and surfaces. – Assemblies with mixed solids and surfaces are OK. – In other situations, users may wish only to import a particular entity type to ignore unnecessary or construction geometry present in the model – Hence, toggling import of solids, surfaces, and/or line bodies is possible ANSYS Workbench – Simulation • For CAD-related settings, importing solid, surface, or line bodies is available March 29, 2005 Inventory #002215 9 -9

CAD & Parameters … Geometry Import (Solid Bodies) Training Manual – Contact regions will automatically be detected between parts in an assembly. • Note that the CAD mating relationship information is not used • Slider controls contact detection tolerance (in ANSYS Professional licenses and above, user can specify value in length units) Model shown is from a sample Solid. Works assembly. ANSYS Workbench – Simulation • Import of solid bodies is supported for all CAD systems March 29, 2005 Inventory #002215 9 -10

CAD & Parameters … Geometry Import (Solid Bodies) Training Manual – A multi-body part is a group of solid bodies. Instead of using different mesh and contact regions between solid bodies, the bodies within a part will share nodes at common interfaces Individual Bodies (non-matching mesh) Single Part (matching mesh) ANSYS Workbench – Simulation • Design. Modeler has concept of “multi-body parts” March 29, 2005 Inventory #002215 9 -11

CAD & Parameters … Geometry Import (2 D Solid Bodies) Training Manual Once imported, the 2 D details can be specified from the Part branch. Plane stress, plane strain or axisymmetric ANSYS Workbench – Simulation • Before importing 2 D geometry you must specify “Analysis Type” is “ 2 D” in the Advanced Geometry options March 29, 2005 Inventory #002215 9 -12

CAD & Parameters … Geometry Import (Surface Bodies) Training Manual – For ANSYS Professional licenses and above, surface body contact is available from the Contact branch – Spot weld definitions can also be used for surface assemblies ANSYS Workbench – Simulation • Simulation also supports import of surface bodies from most CAD systems March 29, 2005 Inventory #002215 9 -13

CAD & Parameters … Geometry Import (Surface Bodies) Training Manual – Instead of using spot welds or edge contact, “joints” in Design. Modeler can ensure that surface bodies share nodes – Surfaces that share edges can also form a part to share nodes Individual Bodies (non-matching mesh) Part of Surface Bodies (matching mesh) ANSYS Workbench – Simulation • In Design. Modeler, “joints” can be used to merge surface bodies together to a “part” March 29, 2005 Inventory #002215 9 -14

CAD & Parameters … Geometry Import (Line Bodies) Training Manual – Line bodies require cross-section definition and orientation, which only Design. Modeler supplies – Line bodies are meshed with beam/link elements – Line bodies can be used in conjunction with surface bodies ANSYS Workbench – Simulation • Line bodies can be imported from Design. Modeler only March 29, 2005 Inventory #002215 9 -15

CAD & Parameters … CAD Associativity Training Manual – Slide 3 showed CAD systems which are associative in Simulation – In some cases, for very large models, the processing time may take a while, so the user can turn off the CAD associativity feature to allow for faster attaching • Turning this feature off will make import faster but will not allow updating of the CAD geometry if changes to the CAD model are made • It is generally not recommended to turn this off unless the user does not need associativity ANSYS Workbench – Simulation • CAD associativity allows updating the CAD geometry in Simulation without needing to redefine material properties, loads, supports, and results Although the toggle is not available for DM and Pro. E, this does not mean that these systems do not support associativity. DM and Pro. E support associativity, just not the ability to toggle March 29, 2005 associativity off. Inventory #002215 9 -16

CAD & Parameters … Save Updated Model (Reader Mode) – For Unigraphics, if the part is updated in reader mode, the updated file can be saved – This is used in conjunction with parameters to update the UG model with new dimensions ANSYS Workbench – Simulation • Reader mode is when a model is attached in Simulation without the CAD system being started up first Training Manual March 29, 2005 Inventory #002215 9 -17

CAD & Parameters … Do Smart Update – Currently, only Inventor and Unigraphics support “Smart Update” feature ANSYS Workbench – Simulation • “Smart Update” is a method by which the updating of assemblies is sped up if the assembly contains unmodified components. Training Manual March 29, 2005 Inventory #002215 9 -18

CAD & Parameters … Attach File via Temp File – When attaching large models, a temporary file to facilitate import can be created/deleted by Simulation if this option is set – If set to “Yes”, a location for the temporary directory can be specified by the user ANSYS Workbench – Simulation • For large models, it may be advisable to turn this feature on. Training Manual March 29, 2005 Inventory #002215 9 -19

CAD & Parameters … Spot Weld Import Training Manual – Although Simulation has some limited spot weld definition capabilities (at vertices only), spot welds can be defined more easily in Design. Modeler and Unigraphics and then imported into Simulation. ANSYS Workbench – Simulation • Spot welds can be used for surface assemblies Not all CAD software support spot weld definitions in a manner usable by Simulation March 29, 2005 Inventory #002215 9 -20

CAD & Parameters … Parameter Import – By turning on this feature (default), any dimension with the user-defined prefix or suffix (default is “DS”) will be imported into Simulation as a parameter • Only dimensions for features will be imported – Once imported, the parameters of various dimensions will appear in the Details view for that particular part. – The use of parameters to change the CAD model or to set up parametric studies will be covered in detail in the next section ANSYS Workbench – Simulation • Dimensions of CAD features can be imported into Simulation Training Manual March 29, 2005 Inventory #002215 9 -21

CAD & Parameters … Parameter Import Training Manual – Design. Modeler: checkmark the dimension, provide Parameter name – Pro/ENGINEER: select dimension, right-click “Properties” – Unigraphics: select dimension and “Edit” – Solid. Works: select dimension, right-click “Properties” – Inventor: select dimension, right-click “Dimension Properties” – Solid Edge: select dimension, right-click “Edit Formula, ” change name – Mechanical Desktop: “Part > Design Variables” and define parameter name. Then change dimension to parameter via “Edit Dimensions” Sample dialog boxes to change dimension name in CAD software ANSYS Workbench – Simulation • Each CAD software has different ways to change the dimension name, so please refer to the CAD documentation March 29, 2005 Inventory #002215 9 -22

CAD & Parameters … Material Property Import Training Manual • The following properties will be imported: Not all CAD software support all material property definition which Simulation supports. Materials imported from CAD will appear in “Engineering Data” branch and will be assigned correctly to parts. – Note that Simulation will not import UG properties in table form (such as temperature-dependent data) – If the material type is changed in CAD, this will be reflected in an update. However, if the values of the material property change in CAD, this will not update to prevent overwriting of user-defined values in Simulation. ANSYS Workbench – Simulation • If “Material Properties Transfer” is enabled, material properties, if defined, will be imported from supported CAD systems March 29, 2005 Inventory #002215 9 -23

CAD & Parameters … Material Property Import Training Manual – Design. Modeler: will import materials from Pro. E, UG, Inventor, but user cannot define material properties inside of DM directly – Pro/ENGINEER: “Edit > Setup: Material > Define/Assign” – Unigraphics: “Tools > Material Properties” – Inventor (to define materials): “Format > Materials” Inventor (to assign): right-click part “Properties: Physical tab” Sample dialog boxes to assign/define material properties in CAD software ANSYS Workbench – Simulation • Each CAD system has different ways to define and assign materials, so please refer to the CAD documentation March 29, 2005 Inventory #002215 9 -24

CAD & Parameters … Coordinate System Import Training Manual – Coordinate systems allow users to define the orientation for direction-dependent loads or contour results • Simulation supports importing of local coordinate systems from some CAD systems – User-defined CS on part or assembly level will be imported – In DM and SW, names come through as-is. In Pro. E, name comes through as part name, followed by CS name in square brackets – Modified/added CS are updated with model ANSYS Workbench – Simulation • Coordinate systems are used in Simulation to apply directional loads or results postprocessing March 29, 2005 Inventory #002215 9 -25

CAD & Parameters … Coordinate System Import Training Manual – Design. Modeler: create Plane, Details view: Export CS – Pro/ENGINEER: “Insert > Model Datum > Coordinate System” – Solid. Works: “Insert > Reference Geometry > Coordinate System” Sample dialog boxes to define coordinate systems in CAD software ANSYS Workbench – Simulation • Each CAD system has different ways to define coordinate systems, so please refer to the CAD documentation March 29, 2005 Inventory #002215 9 -26

CAD & Parameters … Named Selections Import Training Manual – Named selections import can be enabled, as shown on the right – If the “group” in the CAD software has the specified prefix (default is “NS”), then it is imported in the Named Selection branch of Simulation ANSYS Workbench – Simulation • If “groups” are defined in the CAD package, these can be brought into Simulation as Named Selections for supported systems. This makes it easier to assign mesh controls or apply loads to entities. March 29, 2005 Inventory #002215 9 -27

CAD & Parameters … Named Selections Import Training Manual – Unless the CAD system allows direct manipulation of the entities, simply providing ‘names’ for geometric entities will not be imported into Simulation. • Interfacing with CAD API via VB or similar scripting languages may be required – Currently, only Pro/ENGINEER and Unigraphics (and Design. Modeler) allow users to ‘rename’ geometric entities such as surfaces. • Pro/ENGINEER only allows one entity per named selection (limited usefulness) • Unigraphics allows for multiple names per named selection, so ‘true’ groups can be created ANSYS Workbench – Simulation • However, note that this Named Selection processing feature is related to CAD API functionality. March 29, 2005 Inventory #002215 9 -28

CAD & Parameters … Named Selections Import Training Manual – Design. Modeler: “Tools > Named Selections” – Pro/ENGINEER: “Edit > Setup: Name > Other” – Unigraphics: select entities, right-click “Properties” Sample dialog boxes to create “named selections” in CAD software ANSYS Workbench – Simulation • Each CAD system has different ways to rename geometric entities, so please refer to the CAD documentation March 29, 2005 Inventory #002215 9 -29

CAD & Parameters … CAD Attribute Import Training Manual – For example, if a CAD system uses a supported kinematics program, the motion loads can be imported into Simulation for subsequent stress analyses – If this feature is turned on, the prefix can be specified. Only attributes with the given prefix (default is “SDFEA” or “DDM”) will be imported into Simulation. ANSYS Workbench – Simulation • The CAD Attribute Import capability can be used to import attribute information from CAD software, including motion loads March 29, 2005 Inventory #002215 9 -30

CAD & Parameters B. Multiple Design Studies Training Manual • Copying branches in the Outline Tree allow users to easily compare different Environments or even different Models One may wish to compare the results of two different load cases, as shown here ANSYS Workbench – Simulation • In many situations, users may wish to perform comparisons of different load cases or even different types of analyses March 29, 2005 Inventory #002215 9 -31

CAD & Parameters … Multiple Design Studies Training Manual – Duplicate the Environment branch when the user is: • Solving multiple load cases • Solving different types of analyses (static, modal, etc. ) – Duplicate the Model branch when the user is: • Comparing different material properties • Comparing different geometry configurations • Comparing different contact conditions • Comparing different mesh densities • After duplicating the appropriate branch, simply make the necessary changes and then resolve the model. ANSYS Workbench – Simulation • To solve different cases, simply duplicate the parent branch – Usually, it is a good idea to rename the branches in the Outline tree to distinguish between the duplicated branches March 29, 2005 Inventory #002215 9 -32

CAD & Parameters … Multiple Design Studies Training Manual Select which branches you want to include in the HTML Report prior to generating it. All input, results, and figures will be included for each branch and labeled appropriately. ANSYS Workbench – Simulation • After duplicating the branch and resolving, the HTML Report will also contain all the cases solved March 29, 2005 Inventory #002215 9 -33

CAD & Parameters … Updating Geometry Training Manual – For example, to compare two different loading conditions, duplicate the Environment branch, then redefine or add/delete any loads or supports, as needed. • However, when dealing with multiple geometry configurations, additional steps are required – Make changes to geometry in the CAD system – Duplicate the Model branch – Select the Geometry branch, then choose “Geometry > Update: Use Geometry Parameter Values” from the Context toolbar This will work only for CAD systems which are associative. After performing the above steps, the geometry for the selected branch will be updated, and so will all materials, contact regions, and loads. ANSYS Workbench – Simulation • For the aforementioned cases, changing the duplicate branch is straightforward March 29, 2005 Inventory #002215 9 -34

CAD & Parameters … Updating Geometry Example Training Manual – The Model branch was duplicated to “Model 2” – “Model 2” was selected and the new geometry was updated – All material assignment, mesh controls, (contact regions), and loads and supports were updated without manual intervention ANSYS Workbench – Simulation • For example, in the model below, geometry changes were made in the CAD software. March 29, 2005 Inventory #002215 9 -35

CAD & Parameters … Sending Parameters and Updating Training Manual • Another way of updating the geometry is to do this from within Simulation – Recall from Section A “Parameter Import” of this chapter that dimensions with a user-defined prefix or suffix (default is “DS”) will import to Simulation as a parameter – If this is performed, each part will have its parameters (i. e. , dimensions) shown in the Details view ANSYS Workbench – Simulation • The method just described is an easy way to perform comparisons of different geometry configurations March 29, 2005 Inventory #002215 9 -36

CAD & Parameters … Sending Parameters and Updating Training Manual – Simulation actually sends the parameters to the CAD software, which regenerates the new model and sends it back to Simulation automatically • Note that the changes in dimensions must be such that a valid geometry can be created in the CAD software. If not, the update will not succeed. ANSYS Workbench – Simulation – The CAD parameters may be changed in the Details view. Then, select “Update > Update: Use Simulation Parameter Values” from the Context toolbar, and Simulation will update the CAD geometry for that Model branch March 29, 2005 Inventory #002215 9 -37

CAD & Parameters … Updating Geometry Notes Training Manual – Only supported CAD systems (noted in the table below) have this feature. The CAD software must be installed locally on the same machine since Simulation uses the CAD API. – If the topology changes, some entity assignments (e. g. , loading on a surface) may need to be redefined since the original item (such as a surface) is redefined. • If the topology changes, this results in the associativity being broken for that topology. This will be indicated with a “? ” in the Outline Tree after an update. ANSYS Workbench – Simulation • It is important to note the following when updating geometry from the CAD system March 29, 2005 Inventory #002215 9 -38

CAD & Parameters … Updating Geometry Notes Training Manual – All loads will have the same values as before, even if volumes, surfaces, or edges change in volume, area, or length: • The magnitude of all loads will remain constant. For example: – If force was applied on a surface and the surface area increased, the force magnitude remains the same but results in the force per unit area decreasing – If pressure was applied on a surface and the surface area increased, the pressure value remains the same, but this results in more force overall being applied on the surface • The orientation of loads will not change, either – For structural loads, if a direction is specified using existing geometry, the direction of the load will not change even though the geometry used for load orientation has changed ANSYS Workbench – Simulation • Important points to keep in mind (continued): March 29, 2005 Inventory #002215 9 -39

CAD & Parameters … Multiple Design Studies Training Manual – It is possible to insert a blank, new Environment branch from the Model branch • After inserting a new Environment branch, this branch will be blank. • Apply loads and request results, as desired – It is also possible to insert a completely different model in the same Simulation database • Go to the Workbench Project page. • Select the topmost project, the link to the “Active CAD Geometry” or to a “Geometry File. ” • Use “Create a new Simulation” to bring in the model into the current Simulation database. ANSYS Workbench – Simulation • Performing multiple design studies does not require that the Environment or Model branch be duplicated. • Set up analysis as usual March 29, 2005 Inventory #002215 9 -40

CAD & Parameters … Multiple Design Studies Training Manual – For example, if a user wants to only solve a single Environment, select that Environment branch from the Outline Tree and click on the Solve button – To solve all Environment or Model branches, select the parent branch and click on the Solve button. All child branches will then be solved sequentially. – To solve multiple Environment or Model branches, Ctrl-select the branches of interest, then click on the Solve button. – The active branch currently being solved will be indicated with a green lightning bolt. ANSYS Workbench – Simulation • To solve multiple branches at once, go to the parent branch and click on the Solve button March 29, 2005 Inventory #002215 9 -41

CAD & Parameters C. Parameter Manager Training Manual – In the case of multiple Model branches, the Simulation database will become large because the mesh and results for each Model branch will be stored – For many cases, this may be a tedious, manual method • In some situations where many cases are being examined, the use of the Parameter Manager may be warranted – The Parameter Manager is useful to see the effect changes of input values have on certain output quantities. This is done in tabular form. – The Parameter Manager is not useful if the user needs to keep contour results, such as mode shapes of different geometries ANSYS Workbench – Simulation • Performing multiple design studies by duplicating the Model or Environment branch is an easy way to compare results March 29, 2005 Inventory #002215 9 -42

CAD & Parameters … Understanding Parameters Training Manual – If a white input text entry in the Details view has a square next to it, it can be used as an input parameter – If a grey informative text entry in the Details view has a square next to it, it can be used as an output parameter – Simply select the square. A blue “P” will appear, indicating that this will be used with the Parameter Manager • Any items without a square cannot be used as a parameter. Moreover, any items not selected with a blue “P” will also not be used by the Parameter Manager Example of input parameters Example of output parameters ANSYS Workbench – Simulation • In Simulation, input and output parameters are used with the Parameter Manager March 29, 2005 Inventory #002215 9 -43

CAD & Parameters … Using the Parameter Manager Training Manual – Browse through the Outline tree and activate any input parameters which will be used (add blue “P”) – Browse through the Solution branch with results and activate any output parameters to be used (add blue “P”) • Use of Results Scoping (covered in Chapter 9) allows the user to query the local results. For example, by scoping results on selected surfaces, the max equivalent stress on the surfaces can be used as an output parameter – Select the Solution branch of the Environment of interest and select the Parameter Manager button – The Parameter Manager worksheet will appear (see next slide) ANSYS Workbench – Simulation • To activate the Parameter Manager: March 29, 2005 Inventory #002215 9 -44

CAD & Parameters … Using the Parameter Manager Training Manual • The “Scenarios” is a table of cases which will be run ANSYS Workbench – Simulation • The Parameter Manager worksheet tab shows the defined input and output parameters under “Definitions” March 29, 2005 Inventory #002215 9 -45

CAD & Parameters … Using the Parameter Manager Training Manual – Under “Scenarios, ” simply right-click to add rows – Each row represents a simulation – White input values can be changed to desired values – The grey output parameters reflect the result values • The last column indicates whether the solution has been performed. The types of status indicators are “Done, ” “Ready, ” and “Obsolete” – The row in bold is what is reflected in the Outline tree • Unlike the Multiple Studies method, the Parameter Manager does not store all results for all cases. The Outline tree will only reflect the last case (bold). – Check items which you want Parameter Manager to solve ANSYS Workbench – Simulation • Each “Scenario” is a simulation which will be run March 29, 2005 Inventory #002215 9 -46

CAD & Parameters … Using the Parameter Manager Training Manual – If CAD parameters are present, ensure that the dimensions result in valid geometry – If any errors are encountered, the Parameter Manager will skip that scenario • After completed, the results for each scenario can be compared easily in the table. – The results can be exported to Excel (right-click on Parameter Manager branch in Outline tree to export) ANSYS Workbench – Simulation • After setting up the scenarios and clicking on the Solve button, the Parameter Manager will sequentially solve each check-marked case March 29, 2005 Inventory #002215 9 -47

CAD & Parameters … Design. Xplorer and Parameters Training Manual Design. Xplorer and Design. Xplorer VT can be used to examine the effect input parameters have on output parameters. After running the analysis, through XY graphs, response surface plots, sensitivity pie charts, and spider plots, the user can get a better understanding of which parameters affect certain output and by what degree. This extends the use of parameters far beyond what is possible with the Parameter Manager. ANSYS Workbench – Simulation • Design. Xplorer and Design. Xplorer VT are Workbench modules allowing users to obtain a full understanding of the relationship between input and output parameters March 29, 2005 Inventory #002215 9 -48

CAD & Parameters D. Workshop 9 Training Manual • Goal: – Use the Parameter Manager to specify changes to the load magnitude and material properties of the model shown below and solve all scenarios at one time. ANSYS Workbench – Simulation • Workshop 9 – Parameter Manager March 29, 2005 Inventory #002215 9 -49

March 29, 2005 Inventory #002215 9 -50