Adding Constraints
For Creo Simulate to perform most types of analyses, you must constrain at least one area of your model. When you apply constraints, Creo Simulate associates the constraints with model geometry. For structural analysis, a constraint is an external limit on the movement of a portion of your model. For thermal analysis, a constraint is an external limit on the temperature of a portion of your model.
You can apply a constraint to a single geometric entity or to multiple entities. When you apply a constraint to multiple entities, Creo Simulate does not allow you to mix entity types, except for points and vertices, and edges and curves. For example, if you specify a point as the first entity, all remaining entities, to which constraint applies, must also be points or vertices.
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Constraints applied to vertices and to multiple datum points in FEM mode are suppressed.
In general, you should plan the placement of your constraints according to the model type. For example, if you are working with a solid model, you should try to place your constraints on surfaces or surface regions rather than points or curves. With shell models, you should try to place your constraints on curves, surfaces, or surface regions, depending on the load type. Although you can place constraints on other entity types, this placement can adversely affect convergence.
When constraining a structural assembly, be aware that you must constrain all independent bodies in the assembly. If the constraint set does not constrain all bodies in the model, Creo Simulate is unable to run the associated analyses.
You can place some types of constraints on a surface that will be compressed to a midsurface edge. When possible, Creo Simulate automatically transfers the constraint from the original surface to the compressed midsurface else the constraints are deleted.
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