[AB08]

Hi,, am very new to OpenFoam....... can sm1 please tell me

Q1) What is the exact function of fvOptions(U) in the UEqn.H file of simpleFoam? (I assumed that it gave the guessed value of the velocity(U) field (am I right) and if so from where does the initial guess come) ??



tmp<fvVectorMatrix> UEqn
(
fvm::div(phi, U)
+ turbulence->divDevReff(U)
==
fvOptions(U)
);

UEqn().relax();

fvOptions.constrain(UEqn());

solve(UEqn() == -fvc::grad(p));

fvOptions.correct(U);


Q2) What is the function of adjustPhi(phiHbyA, U, p); in the pEqn.H of simpleFoam?



{
volScalarField rAU(1.0/UEqn().A());
volVectorField HbyA("HbyA", U);
HbyA = rAU*UEqn().H();
UEqn.clear();

surfaceScalarField phiHbyA("phiHbyA", fvc::interpolate(HbyA) & mesh.Sf());
adjustPhi(phiHbyA, U, p);

fvOptions.relativeFlux(phiHbyA);

// Non-orthogonal pressure corrector loop
while (simple.correctNonOrthogonal())
{
fvScalarMatrix pEqn
(
fvm::laplacian(rAU, p) == fvc::div(phiHbyA)
);

pEqn.setReference(pRefCell, pRefValue);

pEqn.solve();

if (simple.finalNonOrthogonalIter())
{
phi = phiHbyA - pEqn.flux();
}
}

#include "continuityErrs.H"

// Explicitly relax pressure for momentum corrector
p.relax();

// Momentum corrector
U = HbyA - rAU*fvc::grad(p);
U.correctBoundaryConditions();
fvOptions.correct(U);
}

[AB08]

Hi,,, i m new to OpenFoam nd need sm help .......

What is the function of fvOptions in the following????

#include "fvCFD.H"
#include "fvIOoptionList.H"
#include "simpleControl.H"

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

int main(int argc, char *argv[])
{
#include "setRootCase.H"
#include "createTime.H"
#include "createMesh.H"
#include "createFields.H"
#include "createFvOptions.H"

simpleControl simple(mesh);

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

Info<< "\nCalculating scalar transport\n" << endl;

#include "CourantNo.H"

while (simple.loop())
{
Info<< "Time = " << runTime.timeName() << nl << endl;

while (simple.correctNonOrthogonal())
{
solve
(
fvm::ddt(T)
+ fvm::div(phi, T)
- fvm::laplacian(DT, T)
==
fvOptions(T)
);
}

runTime.write();
}

Info<< "End\n" << endl;

return 0;
}

[cyang]

I also have the same questions. Does anyboody know the answers?

[AB08]

Hey cyang,, i dont have the answers yet....but hv a look here ,,might help

http://www.cfd-online.com/Forums/ope...sportfoam.html