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Courant number

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Old   December 26, 2008, 01:42
Default hi, i am doing a simulation
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weihong yao
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hi,
i am doing a simulation,why the courant number get smaller as the time go?does anyone meet the problem ever?
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Old   December 26, 2008, 04:28
Default hi, which kind of solver do
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hi,

which kind of solver do you used for your case?

Bye
Tian
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Old   December 29, 2008, 15:27
Default sometimes it can happen, basic
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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
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Old   December 30, 2008, 04:03
Default now it is ok! thank you!
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now it is ok!
thank you!
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Old   December 30, 2008, 04:15
Default is there someone good at write
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is there someone good at write new BC?I AM in trouble in it.could someone give me a hand.
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Old   January 5, 2009, 04:25
Default Hi, FOAMers, I am learning
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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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