×
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

Composites and Mechanica

Composites and Mechanica

Composites and Mechanica

(OP)
I tried doing a verification model (simply supported beam) today with a composite sandwich and got very different results. Any thoughts?

Method 1: All solid elements were used for both the thick core material and the laminate. The material properties for the core is isotropic (foam) and the laminate is orthotropic. The problem with this is that meshing is poor for such a thin laminate compared to the core.

Method 2: Core was made with solid elements and laminate was done with shell elements (mid plane extraction from above model). The results between the two methods are drastically different (about 5.75x different!).

The deflection with the all solid elements was alot less then that of the shell+solid configuration. I am trying to figure out why and can't think of the reason so far. I would very much appreciate any insight into this.

Thanks!

RE: Composites and Mechanica

Yous should post this question in the Mechanica Forum:
http://www.eng-tips.com/threadminder.cfm?pid=828

In method 2, how are your shells attached to the solid elements - if they are not attached, this might explain the larger deflection

RE: Composites and Mechanica

(OP)
I think the shells were attached well...I did a modal analysis to see for sure if the shells would move with the core correctly and it did. The interface during meshing was "pink" so it looks like they were bonded as intended.

Thanks for the link to the mechanica forum.

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