×
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

pipe elbow stress modelling
2

pipe elbow stress modelling

pipe elbow stress modelling

(OP)
I am trying to develop a model for an elbow in thick-walled power piping where the wall thickness is non-semitrical due to errosion / corrosion.  This model is not one of the standard models in ANSYS or Abaqus which are the two FEA programs that are available to me.  Thanks for your help.

RE: pipe elbow stress modelling

Is there a question here?

RE: pipe elbow stress modelling

the question is, how does one model a non-circular form, as the original circle is eroded and is not an exact circle.

answer: do it with splines/ curves, but it will be somewhat difficult.
if you have autocad (or similar free program), you can cut the pipe,  photograph its profile, insert into drawing and draw the shape based on it.
then you can import it into abaqus somehow (dxf, dwg) or make a 3d model in autocad.

http://cad-notes.com/2011/06/how-to-embed-image-to-autocad-drawing/

RE: pipe elbow stress modelling

(OP)
I am sorry that I was not clear.  I have ultrasonic inspection data that indicates thinning of a thick walled elbow and this thinning is non-symmetrical.  Based on this data I can develop a reasonable guess as to the wall thickness at various locations.  I have access to ansys and abaqus be neither one has a model in the example data that I can build upon.  Does any one know where I could obtain a model for either of these programs or is there another program that I should look into.  Thanks for your help.

RE: pipe elbow stress modelling

When I have been faced with a similar problem, I developed a python (for ABAQUS) or APDL (for ANSYS) script that modifies the mesh of an ideal elbow, based on the UT data.  The toroidal geometry of the elbow makes the math rather complicated (have you ever done geometry in toroidal coordinate systems before??).

ANSYS has the advantage of being able to use a local toroidal coordinate system built-in.  ABAQUS has no such thing.  If I had the choice, I know which program I would use...

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