CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Meshing & Mesh Conversion

checkmesh failed

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   August 20, 2013, 09:44
Default checkmesh failed
  #1
Member
 
Kai Zhang
Join Date: Jan 2013
Location: yokohama, Japan
Posts: 69
Rep Power: 3
kkpal is on a distinguished road
dear all,

I am simulating flow around cylinders recently. I added some rings around the cylinder which looks like the picture below. However, it seems there's something wrong with the mesh because this message bumps out when i run checkMesh:

Code:
 Mesh non-orthogonality Max: 180 average: 17.0344
 ***Number of non-orthogonality errors: 27720.
  <<Writing 27720 non-orthogonal faces to set nonOrthoFaces
also, some values like Cd and Cl produced by the simulation are far from correct.

I believe the non-orthogonality of the mesh happens in the region where the ring is placed, as is shown in the second picture. Is there any strategy of meshing to avoid this kind of problem? BTW I'm using gmsh as the mesh generator.

thanks in advance!
Attached Images
File Type: jpg shape.jpg (62.2 KB, 11 views)
File Type: jpg mesh.jpg (93.6 KB, 16 views)
kkpal is offline   Reply With Quote

Old   August 20, 2013, 11:11
Default
  #2
Member
 
Elo´se
Join Date: Jul 2012
Location: Trondheim, Norway
Posts: 98
Rep Power: 4
Eloise is on a distinguished road
Hi,

I'm not sure how you can avoid the non-orthogonal faces. But if you want to locate them, you can run the command
Code:
foamToVTK -faceSet nonOrthoFaces
You can then visualize the non orthogonal faces in ParaView and understand where they come from.

Regards,
Elo´se
Eloise is offline   Reply With Quote

Old   August 21, 2013, 00:03
Default
  #3
Member
 
Kai Zhang
Join Date: Jan 2013
Location: yokohama, Japan
Posts: 69
Rep Power: 3
kkpal is on a distinguished road
Thanks for your help! !
It helped me to locate the bad meshes, although i still can not figure out where the problem is

Quote:
Originally Posted by Eloise View Post
Hi,

I'm not sure how you can avoid the non-orthogonal faces. But if you want to locate them, you can run the command
Code:
foamToVTK -faceSet nonOrthoFaces
You can then visualize the non orthogonal faces in ParaView and understand where they come from.

Regards,
Elo´se
kkpal is offline   Reply With Quote

Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Foam::error::printStack(Foam::Ostream&) with simpleFoam -parallel U.Golling OpenFOAM 29 May 29, 2014 22:02
Initial conditions for uniform flow andreas OpenFOAM 5 November 16, 2012 15:00
ParaView/Parafoam error when making animation Disco_Caine OpenFOAM Paraview & paraFoam 6 September 28, 2010 09:54
user subroutine error CFDUSER CFX 2 December 9, 2006 06:31
user defined function cfduser CFX 0 April 29, 2006 10:58


All times are GMT -4. The time now is 03:11.