×
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

MAX. PENETRATION, MAX. CONTACT FORCE ERROR and NEGATIVE EIGENVALUES

MAX. PENETRATION, MAX. CONTACT FORCE ERROR and NEGATIVE EIGENVALUES

MAX. PENETRATION, MAX. CONTACT FORCE ERROR and NEGATIVE EIGENVALUES

(OP)
Hello,

I'm doing a simulation in abaqus standard and i wont to know if MAX. PENETRATION, MAX. CONTACT FORCE ERROR and NEGATIVE EIGENVALUES is a problem or i can stay with them? If yes, how can i fix them and how they afect my results.

Some exemples:
"***WARNING: THE SYSTEM MATRIX HAS 23 NEGATIVE EIGENVALUES."

"MAX. PENETRATION ERROR 2.51836E-09 AT NODE SUPORTEPE-31-1.904 OF CONTACT
PAIR (ASSEMBLY_S_SURF-822,ASSEMBLY_M_SURF-849)
MAX. CONTACT FORCE ERROR -77.7828E-06 AT NODE SUPORTEPE-32-1.379 OF CONTACT
PAIR (ASSEMBLY_S_SURF-701,ASSEMBLY_M_SURF-704)
THE ESTIMATED CONTACT FORCE ERROR IS OUTSIDE OF CONVERGENCE TOLERANCES."

"MAX. PENETRATION ERROR 40.3043E-09 AT NODE SUPORTEPE-25-1.20 OF CONTACT
PAIR (ASSEMBLY_S_SURF-829,ASSEMBLY_M_SURF-828)
MAX. CONTACT FORCE ERROR 794.025E-06 AT NODE SUPORTEPE-23-1.10226 OF
CONTACT PAIR (ASSEMBLY_S_SURF-572,ASSEMBLY_M_SURF-842)
PENETRATION ERROR TOO LARGE COMPARED TO DISPLACEMENT INCREMENT."

Thank you.

RE: MAX. PENETRATION, MAX. CONTACT FORCE ERROR and NEGATIVE EIGENVALUES

If the analysis find convergence in later iterations and the results look plausible, then you don't have to worry.

RE: MAX. PENETRATION, MAX. CONTACT FORCE ERROR and NEGATIVE EIGENVALUES

(OP)
Okey, Thanks!

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


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close