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

nagative volume

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   October 10, 2013, 10:59
Default nagative volume
  #1
Member
 
shahrbanoo
Join Date: Mar 2013
Posts: 63
Rep Power: 13
shahrbanoo is on a distinguished road
Hi dears...
What does it mean when we have negative volume in mesh?
how it happens?
thanx...
shahrbanoo is offline   Reply With Quote

Old   October 11, 2013, 05:33
Default hi Dear
  #2
New Member
 
saeed
Join Date: Feb 2013
Posts: 19
Rep Power: 13
saeed115 is on a distinguished road
maybe it happen when your mesh's are complicated in together and have overlap volume........
saeed115 is offline   Reply With Quote

Old   October 11, 2013, 13:03
Default
  #3
Senior Member
 
Ashwani
Join Date: Sep 2013
Location: Hyderabad
Posts: 154
Rep Power: 12
AshwaniAssam is on a distinguished road
Negative volumes are normally reported when your geometry contains very small "loops"(the first cell of the boundary layer extends beyond the edge of your geometry)near the curved edges. You can check the following link.
http://www.cfd-online.com/Forums/flu...lume-mesh.html
AshwaniAssam is offline   Reply With Quote

Old   October 22, 2013, 18:22
Default
  #4
New Member
 
SsS
Join Date: Oct 2013
Posts: 5
Rep Power: 12
SATHYA0606 is on a distinguished road
Negative volumes occurs in the mesh because of the improper aspect ratio of the elements. It becomes a serious issue once if you try to deform the mesh. You can eliminate these negative volumes by using grid utility application that comes with your gird generator package.
SATHYA0606 is offline   Reply With Quote

Old   October 28, 2013, 03:45
Default
  #5
Senior Member
 
Rami Ben-Zvi
Join Date: Mar 2009
Posts: 155
Rep Power: 17
Rami is on a distinguished road
You may also get negative volumes also if you have left-handed cells. E.g., in a 2D unstructured grid, when the mesher expect cell nodes indices numbered i-j-k-l in a counterclockwise direction, and you input some cells in clockwise direction.
Rami is offline   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
[Other] mesh airfoil NACA0012 anand_30 OpenFOAM Meshing & Mesh Conversion 13 March 7, 2022 18:22
how to set periodic boundary conditions Ganesh FLUENT 15 November 18, 2020 07:09
Problem of simulating of small droplet with radius of 2mm liguifan OpenFOAM Running, Solving & CFD 5 June 3, 2014 03:53
On the damBreak4phaseFine cases paean OpenFOAM Running, Solving & CFD 0 November 14, 2008 22:14
[blockMesh] Axisymmetrical mesh Rasmus Gjesing (Gjesing) OpenFOAM Meshing & Mesh Conversion 10 April 2, 2007 15:00


All times are GMT -4. The time now is 03:41.