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Can I make ramped CONSTRAINT EQUATIONS?

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Hup

Mechanical
Jan 13, 2006
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CZ
Hello!

I use constraint equations (CEs) for preloading internal nonlinear parts in my model - basically sets of rolling bearings. The problem is that the immediate introduction of the CEs provides very sharp loading effect and causes convergency difficulties.

I can explain the problem on a simplified 3-node model with a 1D nonlinear spring which looks like:

D*CE*/\/\*D

Legend:
* node
/\/\ combin39
D displacement constraint on a particular node
CE preloading constraint equation between both nodes

Question: Can I smooth up the introduction of CEs? What about gradually increasing constant terms in CEs? There are a lot of CEs in my full model, so restarting and changing the constant terms manually would be very inconvenient.

Any ideas? Thanks!
 
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