convergence criterion
Altair EmployeeHello,
i have a problem with my non-linear simulation. In my Assambly are two sheets of shell elements, which are connected with skrews (realised with beam and rbe2-Elements).
Between these sheets i designed 'contact surfaces', according this discription:
My run summary told me:
A fatal error has occurred during computations:
*** ERROR # 941 ***
NON-CONVERGENT NONLINEAR ITERATIONS FOR SUBCASE 6
Suggestions:
ANALYSIS COMPLETED.
Results are available. I beleive, that the displacements are to big for the solver. Can this be serious?
My Questions:
Is it true, that the Solver put the Force step by step higher?
How can i read the intermediate data out?
How can i change the convergence criterion?
best regards
Answers
-
Hi BeMa86
Can you increase the NINC and MAXITER values in NLPARM card and check if your run converges or not?
Also, use PARAM,EXPERTNL,YES and CONTPRM,STIFF,SOFT
0 -
See - Linear and Non linear analysis, iteration, increment, step etc explanation topic in the optistruct forum.
Also see User's Considerations for Nonlinear Convergence in help - Altair OptiStruct > User's Guide > Structural Finite Element Analysis > Solution Sequences > Nonlinear Quasi-Static Analysis
0 -
Thanks a lot.
I change the distance of the two sheets and now it works perfectly. The distance now is bigger and the offsets of the elements are adepted.
I don´t understand the reason for convergence.
0
