Working With Imported Geometry: Contact Types for Simulation

1. Working With Imported Geometry: Contact Types for Simulation • Overview of contact types between components • Demonstration and discussion of bonded vs. surface contact types • Mapping of contact type names between Autodesk® Inventor® and Autodesk® Simulation Multiphysics

2. Section 1 Module 4 Page 1 Working With Imported Geometry Contact Types for SimulationOverview • Often, analysis of an assembly is desired, and how the components of the assembly interact need to be defined. • FEA simulation software has multiple ways two surfaces can come in contact, and these are called contact types. • The following is a discussion of each contact type with Autodesk® Simulation Multiphysics and how it behaves.

3. Section 1 Module 4 Page 2 Working With Imported Geometry Contact Types for Simulation Contact types within FEA software • Most FEA software have the following set of contact types: • Bonded, which is usually the default • Surface • Welded • Free/No Contact • Sliding/No Separation • Separation/No Sliding • Edge • Autodesk® Simulation Multiphysics can also create automatic contact pairs between parts. • Friction is an option that can be turned on for any contact pair.

4. Section 1 Module 4 Page 3 Working With Imported Geometry Contact Types for Simulation Mapping of Names: Autodesk® Inventor® vs. Autodesk® Simulation Multiphysics Autodesk® Simulation Multiphysics • Bonded • Surface • Welded • Free/No Contact • Sliding/No Separation • Separation/No Sliding • Edge • (No Equivalent) • (No Equivalent) • (No Equivalent) Autodesk® Inventor® • Bonded • Separation maps as Surface • (No Equivalent) • (No Equivalent) • Sliding/No Separation • Separation/No Sliding • (No Equivalent) • Shrink Fit/Sliding • Shrink Fit/No Sliding • Spring

5. Section 1 Module 4 Page 4 Working With Imported Geometry Contact Types for Simulation Contact Types • Bonded—This is the default contact between two parts, wherever surfaces are in contact. It behaves as if the two parts are glued together, like they are made from one piece of material. For example, use this for bolts clamping plates together, where the coefficient of friction is very high and the pieces will not move relative to one another.

6. Section 1 Module 4 Page 5 Working With Imported Geometry Contact Types for Simulation Contact Types • Surface—When bonded is inappropriate, a surface contact is often used. This allows two surfaces to freely move away from one another under loading conditions, but they cannot move towards or through each other. A shaft in a hole is an example of where a surface contact might be used. Friction might also be turnedon to better simulate actual conditions.

7. Section 1 Module 4 Page 6 Working With Imported Geometry Contact Types for Simulation Contact Types Welded—This contact type is convenient for welded structures, where the outer edges of two parts are bonded, but the interior edges are not, such as shown below: • Free/No Contact—This means that the two parts do not interact with one another. No loads are transferred from one part to the other, even if they come in contact.

8. Section 1 Module 4 Page 7 Working With Imported Geometry Contact Types for Simulation Contact Types • Sliding/No Separation—This contact type allows two surfaces to slide freely past each other, but they are not allowed to gap as the loading is applied. • Separation/No Sliding—Thisis the opposite of the above, where the coefficient of friction is extremely high, so loads applied to the parts will cause them to separate, but not slide along one another.

9. Section 1 Module 4 Page 8 Working With Imported Geometry Contact Types for Simulation Contact Types • Edge—This contact type is much like welded, but can be used along any edge for any length. • Create Contacts Between Parts—Thisis a feature that automatically creates contact pairs between parts. It is best to define contact surfaces based on knowledge of the design than to rely on defaults used for automatic contact pairs. • Settings—Under settings, friction can be turned on, and the coefficient of friction can be set. This is also where the tolerance angle between two surfaces being “in contact” is set.

10. Section 1 Module 4 Page 9 Working With Imported Geometry Contact Types for Simulation Summary • Overview of contact types between components • Demonstration and discussion of bonded vs. surface contact types • Mapping of contact type names between Autodesk® Inventor® and Autodesk® Simulation Multiphysics • The video will demonstrate how to define a contact type between two components in Autodesk® Simulation Multiphysics. • The CAD yoke assembly will be used, along with two pins that are assembled into the holes of the yoke.