CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Main CFD Forum

Unstructured Prism Layers for Boundary Layer Resolution...

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

Reply
 
LinkBack Thread Tools Display Modes
Old   April 13, 2012, 22:03
Default Unstructured Prism Layers for Boundary Layer Resolution...
  #1
Senior Member
 
Robert
Join Date: Sep 2010
Posts: 146
Rep Power: 6
lordvon is on a distinguished road
Hello all,

I have seen unstructured prism layers (they are rectangular prisms cut in half in 3D and rectangles cut along the diagonal into triangles for 2D) being suggested for boundary layer meshing. I havent used them but I am interested. But I am worried; dont these have horrible skew? How do they actually perform in practice?
lordvon is offline   Reply With Quote

Old   April 14, 2012, 03:21
Default
  #2
Far
Super Moderator
 
Far's Avatar
 
Sijal Ahmed Memon (turboenginner@gmail.com)
Join Date: Mar 2009
Location: Islamabad Pakistan
Posts: 3,885
Blog Entries: 6
Rep Power: 37
Far will become famous soon enoughFar will become famous soon enough
Send a message via Skype™ to Far
Quote:
General Point of View
In automobile industry use of prism inflation (aka boundary layer) in very popular. For many complex geometries this is the only solution.

If you have ever tried the Pointwise's anisotripic tetra meshing (T-Rex) http://www.pointwise.com/T-Rex/, you will notice that thier quality is inferior to prism mesh. (These are my personnel comments from my limited knowledge, If someone has more knowledge then pls correct me)

This is the one of the strong point of ANSYS meshing and ICEM CFD.


Quote:
I have seen unstructured prism layers (they are rectangular prisms cut in half in 3D and rectangles cut along the diagonal into triangles for 2D) being suggested for boundary layer meshing.
Do you have more info for this particular technique and posting few pics would help alot to comment further.
Far is offline   Reply With Quote

Old   April 15, 2012, 15:12
Default
  #3
Senior Member
 
John Chawner
Join Date: Mar 2009
Location: Fort Worth, Texas, USA
Posts: 207
Rep Power: 8
jchawner is on a distinguished road
Hello Robert and Far:

Far, I'm going to have to challenge your comment regarding the relative quality of Pointwise's T-Rex method relative to what you call "prism mesh."

T-Rex generates high-aspect ratio tets. They are of good quality because one of the included angles is roughly 90 degrees. While that's OK unto itself, the T-Rex method includes an optional post-processing step that combines 3 T-Rex tets into a single prism. This prism is of good quality because all three of the lines off the base triangle are roughly 90 degrees.

Best Regards
__________________
John Chawner / jrc@pointwise.com / www.pointwise.com
Blog: http://blog.pointwise.com/
on Twitter: @jchawner
jchawner is offline   Reply With Quote

Old   April 15, 2012, 15:36
Default
  #4
Far
Super Moderator
 
Far's Avatar
 
Sijal Ahmed Memon (turboenginner@gmail.com)
Join Date: Mar 2009
Location: Islamabad Pakistan
Posts: 3,885
Blog Entries: 6
Rep Power: 37
Far will become famous soon enoughFar will become famous soon enough
Send a message via Skype™ to Far
I have been using the Gridgen since Release 15.09. And I am really inspired by the relative ease of creating and moving connectors and domains from one location to other location. Gridgen's elipitic solver is also of high quality.

As I already said these comments regarding T-Rex developed by Pointwise reflects my very limited knowledge. I am interested to explorer more about this.

Now my inclination is more towards the ICEM's prism meshing combined with other methods.
Far 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
Adding layers goes wrong with SnappyHexMesh Elise OpenFOAM Native Meshers: snappyHexMesh and Others 1 April 22, 2013 02:32
No layers in a small gap bobburnquist OpenFOAM Native Meshers: snappyHexMesh and Others 2 November 25, 2012 08:54
ICEM Prism Layer transition between surface with prism layers and one without TWaung ANSYS Meshing & Geometry 2 October 12, 2009 14:56
Trimmer & prism layer peresah STAR-CCM+ 6 October 6, 2009 14:39
errors Fahad Main CFD Forum 0 March 23, 2004 13:20


All times are GMT -4. The time now is 09:43.