Convergence problem

[tito662]

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?

 

[mizzjoey]

Hi.

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

regards,
jo

 

[tito662]

How do i adjust the rotation tolerance?

 

[mrgoldthorpe]

Use *CONTROL

 

[mizzjoey]

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.