Physical Contact Problem not solving


#1

I have a model with two parts. It’s basically two cups that set into two other cups. The top edge between the two parts is bonded and then the bottom of each pocket has a bonded contact to simulate a screw. I ran this problem as a linear problem without any issues and then I converted it to a nonlinear problem and it also ran (in about 45 minutes).

On my third simulation (Keystone Wall Attach) I removed the bonded contacts in the bottom of the pockets and I added two physical contacts on the rear wall of each pocket. Originally it was giving me an error but nothing was in the log. I was finally able to get it to run longer, three hours before I killed the job. There are some warnings or errors in french which I do not understand.

If anyone can take a look at this I would appreciate it. It’s probably something really simple but I am drawing a blank.

https://www.simscale.com/projects/cjquijano/hinge_pockets/

Thanks!
Christopher


#2

Hi,

the message: A> <Contact_22

is a warning that your penalty coefficient is to low for your contact problem.
I found a nice hint in the code_aster forum. https://www.code-aster.org/forum2/viewtopic.php?id=20893 The suggestion was, to take the E-Modulus of the “softest” part and divide this value with the characteristic mesh length of the contact region. It is also a good idea to mesh the master surface coarser than the slave surface. Approx. two times coarser. If you have curved surfaces, than it could help to switch the master/slave assignment. The master surface is, in most cases, the surface of the stiffest part but unfortunately this is not always true.

BTW you should improve the mesh, because in the log file is also a warning about the mesh quality.

HTH

Michael


#3

Thanks @mwasim!

I thought it might be something with the penalty coefficient but I was trying softer values not larger values.

Christopher