CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > FLUENT

Check case help

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   June 27, 2011, 17:33
Default Check case help
  #1
New Member
 
J. Robbins
Join Date: Jun 2011
Posts: 3
Rep Power: 15
jarobbins3 is on a distinguished road
hey guys im getting this error for check case..

"maximum cell skewness is greater than 0.98. consider improving the mesh quality before proceeding with your simulation."

also in the text window
"skewness exceeded 0.98 at 15 cells on thread ID = 3.Skewness exceeded 0.98 at 15 cells on thread ID = 3."

can anyone explain:
-What it cell skewness is?
-if this is causing in major errors in the caculations?
-and possible solutoins.

thanks!
jarobbins3 is offline   Reply With Quote

Old   June 28, 2011, 02:23
Default
  #2
Super Moderator
 
-mAx-'s Avatar
 
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41
-mAx- will become famous soon enough
your mesh contains cells with poor quality.
http://my.fit.edu/itresources/manual...equiangle_skew

Fix this issue by modifiying topology (merge,split, etc...) and/or remeshing
__________________
In memory of my friend Hervé: CFD engineer & freerider
-mAx- is offline   Reply With Quote

Old   June 30, 2011, 11:21
Default
  #3
Member
 
Adrien Lemoine
Join Date: Jun 2011
Location: Paris,France
Posts: 31
Rep Power: 15
AdrienL is on a distinguished road
A simulation with cell skewness greater than 0.98 will run but will give awful results such as acceleration of the flow in the middle of nowhere.

You should thing about remeshing the surface mesh (surface skewness < 0.5 will help you to have a cell skewness < 0.9), or using tools such as auto node move (in Tgrid 3d)

Adrien

Btw, to have good results the cell skewness should be less than 0.9 at least
__________________
-------------------------------------------
Plz add reputation if the answer is correct

A cœur vaillant rien d'impossible
------------------------------------------
AdrienL is offline   Reply With Quote

Old   June 30, 2011, 12:55
Default
  #4
New Member
 
J. Robbins
Join Date: Jun 2011
Posts: 3
Rep Power: 15
jarobbins3 is on a distinguished road
Thanks for the help, im using workbench to generate my mesh. What are there imputs that are variable to limit the skewness?
jarobbins3 is offline   Reply With Quote

Old   June 30, 2011, 17:43
Default
  #5
Member
 
Adrien Lemoine
Join Date: Jun 2011
Location: Paris,France
Posts: 31
Rep Power: 15
AdrienL is on a distinguished road
Sorry, can't help you with workbench. I never used it, but you have to make your triangular mesh as equilateral as possible and then the cell skewness will be good too
__________________
-------------------------------------------
Plz add reputation if the answer is correct

A cœur vaillant rien d'impossible
------------------------------------------
AdrienL is offline   Reply With Quote

Reply

Tags
check case, mesh


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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
use batch mode to run an unsteady case PaulineP FLUENT 9 April 4, 2019 09:18
Is Playstation 3 cluster suitable for CFD work hsieh OpenFOAM 9 August 16, 2015 15:53
Superlinear speedup in OpenFOAM 13 msrinath80 OpenFOAM Running, Solving & CFD 18 March 3, 2015 06:36
[snappyHexMesh] Editing the motorBike case, loading diffirent .stl btgyd OpenFOAM Meshing & Mesh Conversion 1 September 26, 2011 18:24
Free surface boudary conditions with SOLA-VOF Fan Main CFD Forum 10 September 9, 2006 13:24


All times are GMT -4. The time now is 19:05.