Abaqus contact controls 2

[scandroglio]

Thanks for help about contact controls.
Now I ask you a question about dumping coefficent.
You said me to obtain the solution in problem involving contact with difficult convergency could be subdivide the analysis in multiple step decrasing dumping coefficent.
You said me the factor in step_1 must be (for example) FACTOR=1 e-06 and in the second one FACTOR=1 e-05.

-Have you make a mistake (FACTOR=1 e-05 is bigger then FACTOR=1 e-06) or is correct?

-To use *STATIC, STABILIZE, FACTOR = 1.00E-05 or *CONTACT CONTROLS, STABILIZE is the same or the effect is different?

Thx and kind regards.

 

[bassmanjax]

If you have ABAQUS v6.7, you could try using the automatic stabilisation. I've tried it on a couple of buckling jobs and it works quite well.

*STATIC, STABILIZE, ALLSDTOL

Using stabilisation in the *STATIC card will add some damping to the structure whereas I guess that contact damping adds damping locally where there is contact.




Martin Stokes CEng MIMechE

 

[bassmanjax]

One other thing - to check how much damping is being applied, you can output ALLSD (viscous damping energy) and plot it against ALLIE (internal energy). By default, ALLSDTOL limits ALLSD to no more than 5% of the internal energy during the analysis.

Martin Stokes CEng MIMechE

 

[deveng100]

STATIC, STABILIZE, FACTOR = 1.00E-05

will lead to global damping...that is to entire model

whereas

CONTACT CONTROLS, STABILIZE

will lead to damping in a particular patch only

Never use both..or system will be error prone