Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Meshing issues - boundary layers

Please login with a confirmed email address before reporting spam

I am trying to model fluid flow up through the inner lumen of a tube, then laterally through pores in the tube wall, and then up through a ring-like channel boardered by said inner tube and another outer tube.

A physics-defined mesh returns "Invalid boundary layer specification" for a seemingly-random inside edge on the outer tube. When I attempt a user-controlled mesh, specifying my own boundary layers, I get the same message. If I fiddle around with different boundaries I receive an "Outer boundary element has wrong number of neighbors."

I'm hoping it is not a problem with how I made my geometry (file is attached). Any ideas?

Thanks so much,

Matt


4 Replies Last Post 7 juin 2013, 12:29 UTC−4

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 24 avr. 2011, 01:28 UTC−4
Alternatively, here is a 2D version of a slice of what I'm trying to accomplish. Of course I receive an error message when attempting to run a parametric sweep with this model as well:

"Failed to find a solution for all parameters,
even when using the minimum parameter step.
No convergence, even when using the minimum damping factor.
Returned solution has not converged."

If anyone could help me with my 3D model first that would be great. Secondary to that would be help troubleshooting the attached 2D axisymmetric model.

Thanks again,

Matt
Alternatively, here is a 2D version of a slice of what I'm trying to accomplish. Of course I receive an error message when attempting to run a parametric sweep with this model as well: "Failed to find a solution for all parameters, even when using the minimum parameter step. No convergence, even when using the minimum damping factor. Returned solution has not converged." If anyone could help me with my 3D model first that would be great. Secondary to that would be help troubleshooting the attached 2D axisymmetric model. Thanks again, Matt


Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 17 juin 2011, 11:42 UTC−4
Hey Matt,

I'm having a similar issue with my model. Specifically, I'm receiving an identical error: "Invalid boundary layer specification" on a seemingly random edge of my model. I was wondering if you or anyone reading this thread has received this or very similar errors and has found any solutions?

Thanks,

Stephen
Hey Matt, I'm having a similar issue with my model. Specifically, I'm receiving an identical error: "Invalid boundary layer specification" on a seemingly random edge of my model. I was wondering if you or anyone reading this thread has received this or very similar errors and has found any solutions? Thanks, Stephen

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 27 juil. 2011, 15:48 UTC−4
I had the same problem (in version 4.2), but it cleared up when I made the mesh coarser (didn't try making it finer).

Catherine
I had the same problem (in version 4.2), but it cleared up when I made the mesh coarser (didn't try making it finer). Catherine

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 7 juin 2013, 12:29 UTC−4
I also had luck in a similar system by deleting the mesh and making a "mapped" mesh instead.
I also had luck in a similar system by deleting the mesh and making a "mapped" mesh instead.

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.