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Convergence problem

Convergence problem

Convergence problem

(OP)
I m modelling the rolling elements of  a bearing by two non linear traction springs between the center of curvatures of the raceways..
Moreover, each center of curvature is coupled to contact zone'(modelled by rigid shells) by a rigid beam .

I have divergence and the following message

AVERAGE MOMENT                      3.43       TIME AVG. MOMENT       3.43    
 LARGEST RESIDUAL MOMENT            2.221E-03   AT NODE      73858   DOF  5
 LARGEST INCREMENT OF ROTATION      0.220       AT NODE      36128   DOF  5
 LARGEST CORRECTION TO ROTATION     0.215       AT NODE      36128   DOF  5
          ROTATION CORRECTION TOO LARGE COMPARED TO ROTATION INCREMENT

Rotation correction.
I tried to decrease the incrementation to 1E-05, and i still have the same probleme.
Any ideas?

RE: Convergence problem

Hi.

Could it be that your rotation tolerance setting is too low? You could try relaxing it. Just a guess here.

regards,
jo

RE: Convergence problem

(OP)
How do i adjust the rotation tolerance?

RE: Convergence problem

Use *CONTROL

RE: Convergence problem

I use

*CONTROLS, PARAMETERS=FIELD, FIELD=DISPLACEMENT
 ,100.0

This sets the displacement ctrl to 100% instead of the 5% default. The values are force tol, disp tol.

I'm sure the documentation has some instructions about rotation ctrl. Try looking up the *Controls.

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