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Implicit Contact Problem

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Zpierre

Bioengineer
Joined
Apr 8, 2010
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3
Location
US
I am currently working on a complex contact problem involving 10 interlocking components made of 2 simple isotropic polymers. I have already set up the problem using ABAQUS explicit and general contact interactions. Frictionless contact and mass scaling was used, but the explicit problem still took extremely long to run.

I keep trying to set up the problem to use Abaqus implicit. Initially I had errors about elements with zero or negative volume, but this was alleviated by eliminating overclosure adjustments. Now I am getting frequent errors about slave surfaces interacting with each other. In addition, the solution never converges. Can anyone help me out here? Should I be using exponential overclosure-pressure?
 
Posting pictures and/or models will greatly help in our understanding of you problem. With the information provided all I can recommend is to only change 1 value from default at a time after reading what it does in the help files.

Rob Stupplebeen
 
Attached is a picture of the problem. The top portion of the assembly has a pressure of 5.3 MPa applied to it. The side and bottom portions have displacement constraints (the side ones can be seen in this picture).

When I try to run this system in explicit, it fails several hours in complaining about wave speed and element deformation. As I stated earlier about the implicit model,I initially had errors about elements with zero or negative volume, but this was alleviated by eliminating overclosure adjustments. Now I am getting frequent errors about slave surfaces interacting with each other. In addition, the solution never converges.
 
 http://files.engineering.com/getfile.aspx?folder=84be9a53-c337-4b43-afb4-772f1cf13162&file=BoundaryConditions.png
Here is an easier to view version of the above image:

boundaryconditions.png
 
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