Convergence Issues - Shell Assembly w/contacts
Convergence Issues - Shell Assembly w/contacts
(OP)
I am having some interesting results for the convergence of stresses in an assembly modeled with shell elements.
Roughly speaking, the model is constructed as follows:
The model has a remote load applied to one component. Both bonded and no penetration contacts are used to link individual components. The model is fully constrained with the combination of component contacts and a fixed support applied to a face of one of the components.
The convergence results are interesting for two reasons:
1. Stresses seem to decrease as mesh size is increased.
2. Some oscillation in stress is evident as mesh size is increased.
Any thoughts on what might be causing this response?
Convergence Data is attached.
Thanks,
Ryano123
Roughly speaking, the model is constructed as follows:
The model has a remote load applied to one component. Both bonded and no penetration contacts are used to link individual components. The model is fully constrained with the combination of component contacts and a fixed support applied to a face of one of the components.
The convergence results are interesting for two reasons:
1. Stresses seem to decrease as mesh size is increased.
2. Some oscillation in stress is evident as mesh size is increased.
Any thoughts on what might be causing this response?
Convergence Data is attached.
Thanks,
Ryano123






RE: Convergence Issues - Shell Assembly w/contacts
The % element/node differnece is actually showing the change in element stress between runs. The actual data is:
Study % element/node difference
1 3
2 1
3 1
4 1
5 0
RE: Convergence Issues - Shell Assembly w/contacts
You may need to round sharp edges to help get rid of this or play with the spring constants on the contact elements.
TOP
CSWP, BSSE
www.engtran.com www.niswug.org
"Node news is good news."
RE: Convergence Issues - Shell Assembly w/contacts
RE: Convergence Issues - Shell Assembly w/contacts
TOP
CSWP, BSSE
www.engtran.com www.niswug.org
"Node news is good news."
RE: Convergence Issues - Shell Assembly w/contacts
In the attached spreadsheet I show von Mises stress probed from a point on the end of a strategically placed split line. I get the same shaped curves when I compare strain energy density between studies.
RE: Convergence Issues - Shell Assembly w/contacts
TOP
CSWP, BSSE
www.engtran.com www.niswug.org
"Node news is good news."