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-   OpenFOAM Running, Solving & CFD (http://www.cfd-online.com/Forums/openfoam-solving/)
-   -   Courant number (http://www.cfd-online.com/Forums/openfoam-solving/58160-courant-number.html)

ivanyao December 26, 2008 02:42

hi, i am doing a simulation
 
hi,
i am doing a simulation,why the courant number get smaller as the time go?does anyone meet the problem ever?

tian December 26, 2008 05:28

hi, which kind of solver do
 
hi,

which kind of solver do you used for your case?

Bye
Tian

antonio_ing December 29, 2008 16:27

sometimes it can happen, basic
 
sometimes it can happen, basically because the solution is converging and the shear is becoming smaller than at the beginning... Usually it could be a good thing

ivanyao December 30, 2008 05:03

now it is ok! thank you!
 
now it is ok!
thank you!

ivanyao December 30, 2008 05:15

is there someone good at write
 
is there someone good at write new BC?I AM in trouble in it.could someone give me a hand.

sxhdhi January 5, 2009 05:25

Hi, FOAMers, I am learning
 
Hi, FOAMers,

I am learning OpenFOAM. Could anyone be kind to tell me what the definition of deltaCoeffs is appearing in the below codes? where is the length scale in the formula?

Thanks

Su Xiaohui

\*---------------------------------------------------------------------------*/

scalar CoNum = 0.0;
scalar meanCoNum = 0.0;

if (mesh.nInternalFaces())
{
surfaceScalarField SfUfbyDelta =
mesh.surfaceInterpolation::deltaCoeffs()*mag(phi)/fvc::interpolate(rho);

CoNum = max(SfUfbyDelta/mesh.magSf())
.value()*runTime.deltaT().value();

meanCoNum = (sum(SfUfbyDelta)/sum(mesh.magSf()))
.value()*runTime.deltaT().value();
}

Info<< "Courant Number mean: " << meanCoNum
<< " max: " << CoNum << endl;

// ************************************************** *********************** //


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