CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > SU2

Is degenration a problem?

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 21, 2014, 02:29
Default Is degenration a problem?
  #1
New Member
 
nilesh
Join Date: Mar 2014
Location: Kanpur / Mumbai, India
Posts: 27
Rep Power: 12
nilesh is on a distinguished road
Hi,
I am creating a 3D mesh using hexahedral elements. In some regions, the hexahedrals are supposed to actually convert into wedges due to overlapping of their sides and some rectangles will consequently get converted to triangles at the boundary surfaces (imagine meshing a cylinder with hexahedrals).
Instead of defining wedge elements seperately, if I declare these elements as hexahedrals with two pairs of distinct nodes having the same coordintes so that geometrically it is actually a wedge, will it cause any error in flow computation?
Similar is the case of defining a rectangle with one repeated coordinate.

Thanks.
nilesh is offline   Reply With Quote

Old   July 21, 2014, 16:00
Default
  #2
Super Moderator
 
Francisco Palacios
Join Date: Jan 2013
Location: Long Beach, CA
Posts: 404
Rep Power: 15
fpalacios is on a distinguished road
Quote:
Originally Posted by nilesh View Post
Hi,
I am creating a 3D mesh using hexahedral elements. In some regions, the hexahedrals are supposed to actually convert into wedges due to overlapping of their sides and some rectangles will consequently get converted to triangles at the boundary surfaces (imagine meshing a cylinder with hexahedrals).
Instead of defining wedge elements seperately, if I declare these elements as hexahedrals with two pairs of distinct nodes having the same coordintes so that geometrically it is actually a wedge, will it cause any error in flow computation?
Similar is the case of defining a rectangle with one repeated coordinate.

Thanks.
Hi,

In principle, it should work. In the past we have found some issues with the gradient computation… our recommendation is to use Green Gauss.

Cheers,
Francisco
fpalacios is offline   Reply With Quote

Old   July 22, 2014, 01:05
Default
  #3
New Member
 
nilesh
Join Date: Mar 2014
Location: Kanpur / Mumbai, India
Posts: 27
Rep Power: 12
nilesh is on a distinguished road
Quote:
Originally Posted by fpalacios View Post
Hi,

In principle, it should work. In the past we have found some issues with the gradient computation… our recommendation is to use Green Gauss.

Cheers,
Francisco
Thank you Sir. Can you please point to a source/paper which talks about the effect of cell degeneration in finite volume computation?
nilesh is offline   Reply With Quote

Reply

Tags
3d grid, hexahedral, su2, wedge


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
UDF compiling problem Wouter Fluent UDF and Scheme Programming 6 June 6, 2012 05:43
Gambit - meshing over airfoil wrapping (?) problem JFDC FLUENT 1 July 11, 2011 06:59
natural convection problem for a CHT problem Se-Hee CFX 2 June 10, 2007 07:29
Adiabatic and Rotating wall (Convection problem) ParodDav CFX 5 April 29, 2007 20:13
Is this problem well posed? Thomas P. Abraham Main CFD Forum 5 September 8, 1999 15:52


All times are GMT -4. The time now is 18:41.