MES Contact Surface Convergence Issue Chattering

[dauto&]

I am running a MES simulation with a frictionless contact surface interface.  The convergence is very very poor and I believe it is because the mesh is contiguous across the contact, i.e. the nodes perfectly align on either side of the contact.  This is shown to be an issue in the white paper http://www.algor.com/news_pub/tech_white_papers/surface_contact/default.asp

My question is, how do I get the nodes to not be aligned?  I am using a CAD model from Rhino and I cannot figure out a way to make the mesh offset at this interface.  I tried deactivating the parts in question one at a time and meshing.  This will get dissimilar meshes but then will put an error flag on one of the parts and not allow for solution until the model is remeshed with both parts active, which then results in a contiguous mesh.

I believe I could get around this by building one of the parts in Algor and controlling its mesh that way, but that is a pain.  Does anyone know an easier way?

Thanks

DS

[ilyas_drawbridge]

Hi DS,

I do not think it is possible to suppress mesh and unsuppress a part followed by running the analysis. Regardless, I think you can set the mesh to not match by setting a few things up.

Analysis Parameters>Contact>Enable smart bonded/welded contact (Refer to wikihelp>types of contact for a detailed explanation on choosing course to fine or vice versa, but either one should have the same effects on the mesh)

3D Mesh Settings>Options>Model>uncheck Use virtual imprinting, check Do not match the mesh of contact pairs when applicable

If the mesh still matches, it might be due to contacts which are applied on those two surfaces. Try to delete those and remesh. I do not know the mesh matching requirements of frictionless contact though, so this may not ultimately solve your problem.

Regards

Ilyas