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Problem with Lagrange multiplier friction forumation

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Adrien

Mechanical
May 9, 2008
4
Good day everyone. I'm actually testing the different friction and contact formulations that Abaqus proposes on a quite simple model : A rubber 2D rectangle sliding on an analytical rigid line. And I have a problem with a particular combination of formulations, what's to say :

- Surface-to-Surface discretization
- Lagrange multiplier friction formulation
- "Hard" contact pressure-overclosure relation (no matter if I use Augmented Lagrange, penalty or direct constraint enforcement)

The algorithm simply doesn't converge. It cuts back five times at the first increment and exits because of "too many attempts made for this increment".
If I change the Surface-to-Surface discretization to a Node-to-Surface one, it converges. If I change the Lagrange multiplier friction formulation to penalty, it works too. And if I use a "Soft" pressure-overclosure relation instead of a "Hard" one, again it converges.
Does anyone have an idea why this particular combination causes such problems ?

Thanks,

Adrien.
 
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