×
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

Constant curvature and constant twist patch tests

Constant curvature and constant twist patch tests

Constant curvature and constant twist patch tests

(OP)
I am trying to understand the details of how a constant curvature and a constant twist patch test are applied, and what the desired results are.

Doing some internet browsing, I found the linked book, which has an example of a constant curvature test and a constant twist test.

http://upetd.up.ac.za/thesis/submitted/etd-0306200...

In the constant curvature patch test, the boundary conditions are zero displacement in x,y,z directions at the upper left node, zero displacement in x and z directions at the lower left node, and zero rotation about the y-axis at both the upper and lower left hand nodes. A bending moment, M is then applied to the upper and lower right hand side nodes.

FEM is then used to calculated the curvature across the patch. If the curvature is constant, the patch test is passed. Is that correct?

In the constant twist patch test, all nodes are restrained in the x and y directions, and three of the four corners are restrained in the z-direction. A force is then applied to the fourth corner in the z-direction.
With this test, I am not sure what the outputs of the test are, and how the test is passed? Can anyone give me a hand?

RE: Constant curvature and constant twist patch tests

for me a patch test is a single element test, and the idea is to compare the FE output with your hand calcs. for me it's not "If the curvature is constant" but i'm more interested in the stress results (the displacements should match well as these are typically the assumption that the FE makes).

Quando Omni Flunkus Moritati

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