×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Contact controls parameter
2

Contact controls parameter

Contact controls parameter

(OP)
Hello,
thanks a lot to all forum for help about force visualization in Abaqus.
Now I have another question about contact controls in Abaqus.
During analysis involving contact surface, when the convergence is difficult I use the following parameters:

*CONTACT CONTROLS, STABILIZE
*CONTACT CONTROLS, AUTOMATIC TOLERANCES
*CONTROLS, ANALYSIS = DISCONTINUOUS

The contact controls STABILIZE added a dumping to stabilize the solution.
I see that this parameter is very "strong" but I'm not sure if "thrust the solution" and give incorrect result.
Is good use this parameter?(this parameter help a lot in instance of not convergence solution)
Is there someone that Can give me other valid contact parameter to convergence the solution in instance of difficult convergence?

Thank and kind regards

RE: Contact controls parameter

Hi,
Yeah it is helpful; indeed ..and most important it decreases that damping to zero by the last increment in the step..so pratically it halps to initiate and give you fairly accurate result bythe end..Only thing don't play with default parameteers too much.
Other options may by global stabilize and tied contact with adjust
REgards
Devashish

RE: Contact controls parameter

2
Try specifiying the damping factor within *static
that is, *static,stabilize,factor=1e-06

Try a multi step analysis, and for each step reduce the damping factor. Therefore you may want to try:

*static,stabilize,factor=1e-06
*static,stabilize,factor=1e-05
*static,stabilize,factor=1e-04


down to
*static,stabilize,factor=1e-01

Remember, that when stabilisation is used with *static, a viscous damping force Fv is introduced, so that ABAQUS solves the equations,

P-I-Fv = 0 (P = Applied Load, I = Internal Load, Fv = Viscous damping)

The inaccuracy is because the additioinal term Fv is introduced into the equation.

WITHOUT stabilisation, ABAQUS will solve P-I=0.

Using stabilisation will make your solution less accurate but if you try running a contact problrm without it, then the chances are that your solution will NOT converge.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources