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

Is it possible to use divergence in the source term of an scalar transport equation?

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   January 8, 2010, 19:53
Default Is it possible to use divergence in the source term of an scalar transport equation?
  #1
New Member
 
Join Date: Jan 2010
Posts: 5
Rep Power: 16
jannnesss is on a distinguished road
Hey everyone!!

I have the following problem. I'm trying to implement "Thermophoretic Force/Velocity" in Ansys CFX12. The thermophoretic velocity/force depends on the temperature gradient, which is easy to get in CFX Pre. I want to include the thermophoretic force because of the effect of depostion on particles in aerosol flows.
But the main problem I have is defining the source term of the scalar transport equation of the particles.
The source term should look like this:
div(rho*N_particle*u_th)
The complete Transport Equation should look like this:
d(rho*N_particle)/dt+div(rho*u*N_particle)=-div((rho*N_particle*u_th)
where N is the transported scalar, rho is the density an u_th is the termophoretic velocity vector.
Is there any possibilty to define this source term with CEL or any other method. Is there a possibilty in CFX to calculate the divergence of a Sourceterm?

Or is it possible to define something like a "slip velocity" for a scalar transport equation? The convection term should then look like this:
div(rho*Psi*(U-+U_slip)) where Psi is the general transported scalar

Thanks a lot!!!!!! I tried a lot by using "diffusive transport equations" (the main idea was to hide the thermophoretic velocity in the duffusioncoefficient) but nothing works.
I'm very thankful for every tip!
With best regards,
Jan

Last edited by jannnesss; January 9, 2010 at 08:37.
jannnesss is offline   Reply With Quote

Reply


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
Problem of SOURCE term gradient in UDS wind Fluent UDF and Scheme Programming 6 December 1, 2022 14:21
Adding implicit source term to momentum equation fs82 OpenFOAM 6 September 23, 2009 03:29
Scalar transport equation dimension problem litonx OpenFOAM Running, Solving & CFD 3 March 2, 2007 06:49
how to set velocity in certain place in CFX5 cfxbeginer CFX 6 July 7, 2003 18:38
How to deal with this energy equation source term? H.S.Fang FLUENT 2 December 27, 2001 06:42


All times are GMT -4. The time now is 20:20.