CFD Online Logo CFD Online URL
Home > Forums > FLUENT

source term udf

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

LinkBack Thread Tools Display Modes
Old   August 14, 2009, 08:54
Default source term udf
Senior Member
Troy Snyder
Join Date: Jul 2009
Location: Akron, OH
Posts: 138
Rep Power: 11
tas38 is on a distinguished road
I am trying to write a udf that adds a momentum source term.

The source term is written in terms of vorticity and vorticity magnitude. As I cannot explicitly extract vorticity and operators such as grad are not available, does anyone have suggestions as to how to write this udf?

consider for example that the source term is grad(abs(vorticity))/(abs(grad(vorticity)){cross}(vorticity)

where vorticity is the vorticity vector and {cross} indicates cross product
tas38 is offline   Reply With Quote

Old   August 14, 2009, 10:44
Join Date: Apr 2009
Posts: 78
Rep Power: 10
tstorm is on a distinguished road
FLUENT stores gradients for user-defined scalars. So, you might try storing those terms as user-defined scalars (i.e., C_UDSI(c,t,0) = vorticity(c,t) ) and then accessing the gradient with C_UDSI_G(c,t,0).
Hope that helps!
tstorm is offline   Reply With Quote


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
gradient source term UDF ak6g08 Fluent UDF and Scheme Programming 0 July 9, 2009 06:37
UDF - Source Term Question Jacques FLUENT 0 December 8, 2008 14:40
DxFoam reader update hjasak OpenFOAM Post-Processing 69 April 24, 2008 01:24
DecomposePar links against liblamso0 with OpenMPI jens_klostermann OpenFOAM Bugs 11 June 28, 2007 17:51
UDF Source Term Units? Brian FLUENT 1 October 24, 2005 09:15

All times are GMT -4. The time now is 19:03.