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PISO Algorithm

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Old   September 4, 2013, 05:26
Post PISO Algorithm
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Hi ,
I am a beginner in OpenFOAM and trying to understand IcoFoam Code.
I have the following problems.
  1. What exactly the following code does all together ? for (int corr=0; corr<nCorr; corr++)
    {
    volScalarField rAU(1.0/UEqn.A());

    volVectorField HbyA("HbyA", U);
    HbyA = rAU*UEqn.H();
    surfaceScalarField phiHbyA
    (
    "phiHbyA",
    (fvc::interpolate(HbyA) & mesh.Sf())
    + fvc::ddtPhiCorr(rAU, U, phi)
    );

    adjustPhi(phiHbyA, U, p);
  2. What is HbyA ?
  3. What do these give us from physical point of view
    • volScalarField rAU(1.0/UEqn.A());why should we consider reciprocate of UEqn.A() ?
    • HbyA = rAU*UEqn.H();
  4. what is the meaning of ddtPhiCorr(rAU, U, phi) ? PLEASE HELP ME......
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Old   September 4, 2013, 06:22
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I would recommend to search for the thesis by Hrvoje Jasak, it contains the explanation of these algorithms, closely following the notation of OpenFOAM (or vice versa)
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Old   September 4, 2013, 06:25
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Thank You
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Old   September 5, 2013, 06:45
Post Doubt on piso
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Hi

Could u please explain why solver takes reciprocal of diagonal elements of velocity matrix...
code is volScalarField rAU(1.0/UEqn.A());?
& whats the out put of the following code HbyA = rAU*UEqn.H(); ?
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Old   October 11, 2013, 01:25
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I am also new to openfoam. My understanding is:
HbyA is H divided by A which equals to UEqn.H()/UEqn.A()= UEqn.H()*1.0/UEqn.A() = rAU*UEqn.H()
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