×
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

Mises stress problem

Mises stress problem

Mises stress problem

(OP)
Hello everyone,

I have a power distribution box with many bus bars and fuses inside. I want to do a static analysis by introducing the pressure of screws on busbars (it looks simple test). There is so many contacts (surface to surface) have modeled. The problem is with correct boundary conditions and pressure of 21 MPa I find in static that mises stress is of 10e4 even 10e5 MPa and deformation and displacement are really big and it's not normal. In brief I can't find the mistake for this case so please if someone has just an idea he can answer me.

Thanks in advance

RE: Mises stress problem

Hi,

Check units. Newton, mm, MPa are good to use. "pressure of screws". Is that preload? If so, did you switch from displacement to an actual force preload?

A linear material model can show high peak stress.

Hard to know but those are my guesses.

Good luck!

RE: Mises stress problem

(OP)
Hello StefCon,

Yes it's a preload, after this first step a modal analysis will be elaborated to extract the natural frequencies of the box and application of mechanical shock to see how it behave. Boundary conditions of the frequency step were used as boundary conditions in the preload and it's not the reality in fact. Preload must not have the same boundary conditions. This modification has corrected the problem and stress becomes logic.

Many Thanks for your answer
Regards

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