error message of Singular matrix in nitsche contact

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When the same problem is solved by penalty and augmented Lagrangian there is no error. But with nitsche, there's the following error:

  • Feature: Stationary Solver 1 (sol17/s1) Failed to find a solution for the initial parameter. Singular matrix.

There are 264 void equations (empty rows in matrix) for the variable comp1.solid.Wfric_p1. at coordinates: (2.65789e-18,0.0248165,-0.0434066), (2.16489e-18,0.0353553,-0.0353553), (1.51957e-18,0.0434066,-0.0248165), (7.86146e-19,0.0483235,-0.0128387), (1.8747e-34,0.05,-3.06162e-18), ...

and similarly for the degrees of freedom (empty columns in matrix). Returned solution is not converged. Not all parameter steps returned.


0 Replies Last Post 15 mag 2024, 09:55 GMT-4
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Hello Carl Xu

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