Contact for Sliding/Telescoping Parts

[dbcox]

Hello everyone,

I have a model created in Inventor 2013 that I need to analyze in Simulation Mecanical 2013.  I have a boxed tube with a slot cut in it.  Within that tube is a smaller tube lined on the outside with wood (sacrificial wear surface).  I have it drawn with a 1/16" between the outer surfaces of wood and the inner surfaces of the outer boxed tube with a slot.  A bracket is connected to the inner tube and is designed to stay within the slot as the inner tube, wood, and bracket move up and down.  As you may suspect, the bracket has a load applied to it.

I cannot seem to figure out how to define the contacts so that the wood does not "bond" to the outer tube.  When I set the contact between the two parts, they do not bond, BUT, the model acts as if the outer tube isn't there.  The wood never contacts the outer tube in the model, it just goes through it.  In other words, the outer tube never "captures" the inner tube/wood.

How do I setup the conacts for sliding/telescoping components?

Thank you!

[AstroJohnPE]

Hi db,

My guess is that contact is setup properly but something else needs to be tweaked.You can confirm that contact elements are created from the Results environment. The command "Results Inquire > Inquire > Model Statistics" will list all of the parts in the model and the element type.

Depending on the analysis type, one of these tips could be the solution to your problem.

• Linear static stress. See the page "Perform Analyses with Gap Elements" in the Help documentation for tips on making the model statically stable. (I believe the 2013 menus use the term "3D springs" instead of "Rigid Boundary" that is used in the documentation.)
• Nonlinear > MES. The load may be applie to quickly, causing the part to accelerate so fast that it is beyond the contact detection range on the first time step. Try a very small load multiplier for the first few steps.
• Nonlinear > Static. Use MES instead.

[zhuangs]

For your model, only "MES with Nonlinear Material Models" analysis type can be used.  To set up surface contact in MES, contact pairs between all the contact surfaces should be defined first.  For a defined contact pair, if contact is missing and penetration happens, my last comment for the following topic might help:

http://forums.autodesk.com/t5/simulation-mechanical-and/cero-friction/m-p/5221795#M7215

-Shoubing