CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Running, Solving & CFD

Problem computing divergence field

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

Reply
 
LinkBack Thread Tools Display Modes
Old   April 1, 2012, 07:06
Default Problem computing divergence field
  #1
New Member
 
Gilles De Neyer
Join Date: Nov 2011
Posts: 18
Rep Power: 5
gdeneyer is on a distinguished road
Hello,

I'm actually trying to compute the divergence field for a laminar compressible flow on a cylinder and I got weird results around the cylinder. I have a zero divergence field inside the structured grid around cylinder and then some fluctuation in the non structured grid.

The code I used for this was just this at the end of my timeloop
volScalarField divField
(
IOobject
(
"divU",
mesh.time().timeName(),
mesh,
IOobject::NO_READ
IOobject::AUTO_WRITE
),
fvc::div(U)
);

Note: the flow is laminar with low Mach number 0.05 using rhoPimpleFoam, in attachment the divergence field with and without the mesh
Attached Images
File Type: jpg grid.jpg (99.8 KB, 16 views)
File Type: jpg nogrid.jpg (25.4 KB, 20 views)
gdeneyer is offline   Reply With Quote

Old   April 2, 2012, 02:34
Default
  #2
Senior Member
 
Alberto Passalacqua
Join Date: Mar 2009
Location: Ames, Iowa, United States
Posts: 1,894
Rep Power: 26
alberto will become famous soon enoughalberto will become famous soon enough
There are a good number of posts explaining that what should be computed is

fvc::div(phi)

and not fvc::div(U).

Best regards,
__________________
Alberto Passalacqua

GeekoCFD - A free distribution based on openSUSE 64 bit with CFD tools, including OpenFOAM. Available as live DVD/USB, hard drive image and virtual image.
OpenQBMM - An open-source implementation of quadrature-based moment methods
alberto 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
Multiphase phase (gas-solid) flow using Eulerian-Granular medel ( divergence problem) jessie FLUENT 3 May 29, 2014 11:05
Divergence problem for species transport model MY FLUENT 3 January 11, 2014 05:46
Problem while running in Highperformance computing environment Phanipavan STAR-CD 1 September 11, 2013 06:42
problem during my computing oliver FLUENT 0 May 31, 2007 08:35
Divergence Free on the Magnetic Field Valdemir Main CFD Forum 1 March 19, 2003 19:33


All times are GMT -4. The time now is 18:17.