×
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

PVC foam constitutive description in ANSYS material model or USERMAT

PVC foam constitutive description in ANSYS material model or USERMAT

PVC foam constitutive description in ANSYS material model or USERMAT

(OP)
Hello everyone,

This is my first post on this forum and I am really hoping that somebody can help me since I am more or less stuck.

Currently I am trying to define the mechanical behaviour, 2D in ANSYS, of a sandwich specimen in 3-point bending (E-glass facing and PVC core).
This particularly concerns the behaviour of the foam material when local indentation occurs.
The model (of the core material) that I am trying to use is based on the polymer foam constitutive model of Deshpande and Fleck. This model is based on the following:
tensile yield of the foam is governed by an elliptical yield surface in von Mises versus mean stress, while in compression the cell walls buckle elastically,
and a maximum principle stress criterion applies (buckling cap in the yield surface).

After studying all the possible non lineair material models in ANSYS I am starting to get convinced that this is impossible with the excisting models.
If this is correct it implies that I have to use the subroutine interface USERMAT.

The quetions:

- Is the assumption correct that there are no models available that can capture the mentioned constitutive model?
- Is it possible to use the usermat3D.F as a base for programming this constitutive model?

If anybody has some thoughts or experience please share.

Peter

ps. if some parts are not clear please let me know  

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