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

Highly skewed elements

Register Blogs Community New Posts Updated Threads Search

Like Tree1Likes
  • 1 Post By Jason

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   August 11, 2005, 11:01
Default Highly skewed elements
  #1
Hengky
Guest
 
Posts: n/a
Dear Forum, I always have highly skewed elements in meshing my geometry. I was wondering if someone could tell me how to avoid those highly skewed elements. Thank you. I appreciate it
  Reply With Quote

Old   August 11, 2005, 12:49
Default Re: Highly skewed elements
  #2
Swarup
Guest
 
Posts: n/a
High skewing can happen due to excessive mesh refinement in case of tri/tetra meshes. the problem can be acute at wall boundaries. why not try other mesh types or work with coarse mesh first and then selectively refine it?

Swarup
  Reply With Quote

Old   August 11, 2005, 13:17
Default Re: Highly skewed elements
  #3
Jason
Guest
 
Posts: n/a
There are a lot of things that can cause highly skewed elements. Lets say you want to mesh a surface with a .1mm Face mesh... but there are two vertices on the surface that are only .0001mm apart... since Gambit will place a node at any vertice, then the third element will be about .1mm away... now you have a triangle with one edge of about .0001mm and two edges of about .1mm... this is a skewed element. This is just one example of what can cause a skewed element... another cause is two edges that come together at an acute angle, the element created in the corner will be skewed... in 3D there's many more possible causes. Every case is unique. It can almost always be attributed back to a problem with the geometry. First you need to find where the skewed elements are (you can use the Examine Mesh Tool... icon on the bottom right of the screen... looks like a yellow grid with a magnifying glass over it). Once you know where they are, you need to think about what's causing them. It's rare that there is a highly skewed element "floating" out in the middle of the volume. If this happens, then it may be due to over refinement. Odds are though that the problem cells are located on a surface and are a result of the geometry. Once you know where they are and what caused the problem, you can work out a way to correct the problem (whether it's merging edges and/or faces, or splitting edges and/or face or actually splitting the volume into smaller, easier to mesh volumes).

Hope this helps, and good luck, Jason
Honey likes this.
  Reply With Quote

Reply


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
Can highly skewed elements create problem?? Sanjay Jain FLUENT 1 April 8, 2008 16:57
help: the volume mesh has highly skewed elements xiaofish FLUENT 3 September 18, 2007 10:51
what to do w/ highly skewed elements? (GAMBIT) mike FLUENT 5 June 2, 2007 23:10
highly skewed elements srikanth Main CFD Forum 1 February 21, 2006 09:15
CFX4.3 -build analysis form Chie Min CFX 5 July 13, 2001 00:19


All times are GMT -4. The time now is 10:40.