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

Obtaining Diffusive Fluxes

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

Reply
 
LinkBack Thread Tools Display Modes
Old   June 16, 2011, 11:29
Default Obtaining Diffusive Fluxes
  #1
Senior Member
 
Illya Shevchuk
Join Date: Aug 2009
Location: Darmstadt, Germany
Posts: 176
Rep Power: 9
linch is on a distinguished road
Hello FOAM_Community,
how can I obtain a diffusive mass flux resulting from solving a species equation:
Code:
    fvScalarMatrix xN2Eqn
    (
             fvm::ddt(rho*alpha1, xN2)
           + fvm::div(rhoPhi, xN2)
           - fvm::laplacian(DN2f, xN2)
           ==
             rhoN2Su
    );
    xN2Eqn.solve();
what I need is a surfaceScalarField jN2f.
xN2Eqn.flux() would return the overall flux. fvc::laplacian(DN2f, xN2) would probably return a volScalarField which equals to the cell flux divergence, right? So what I thought about is something like:
Code:
volScalarField jN2 = fvc::laplacian(DN2f, xN2);
surfaceScalarField jN2f = fvc::interpolate(jN2);
Is this way completely wrong? Even if it works, I suspect I don't necessarily get the same fluxes like those, resulting from the solution of the xN2Eqn. I think there must be a better way.

regards,
linch is offline   Reply With Quote

Old   June 20, 2011, 05:29
Default
  #2
Senior Member
 
Illya Shevchuk
Join Date: Aug 2009
Location: Darmstadt, Germany
Posts: 176
Rep Power: 9
linch is on a distinguished road
The reason for doing this is: mass diffusion causes enthalpy transport. That's why I need diffusive mass fluxes from the species equations.
linch 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
CANTERA code to get pure species mass fluxes gemmafebrer Main CFD Forum 0 October 19, 2010 11:42
Help: diffusive flux BC at wall Quarkz Main CFD Forum 7 July 17, 2005 11:24
Printing Convective & Diffusive Fluxes Rajiv Shekhar Phoenics 1 May 17, 2005 08:00
Roe upwind fluxes!! Magesh Main CFD Forum 2 July 17, 2003 11:35
UDF Face Fluxes & Partitioned Grids Greg Perkins FLUENT 0 April 6, 2001 01:50


All times are GMT -4. The time now is 04:27.