openfoam/applications/solvers/multiphase/bubbleFoam/pEqn.H

{
    surfaceScalarField alpha1f(fvc::interpolate(alpha1));
    surfaceScalarField alpha2f(scalar(1) - alpha1f);

    volScalarField rAU1(1.0/U1Eqn.A());
    volScalarField rAU2(1.0/U2Eqn.A());

    surfaceScalarField rAU1f(fvc::interpolate(rAU1));
    surfaceScalarField rAU2f(fvc::interpolate(rAU2));

    U1 = rAU1*U1Eqn.H();
    U2 = rAU2*U2Eqn.H();

    surfaceScalarField phiDrag1
    (
        fvc::interpolate(alpha2/rho1*dragCoef*rAU1)*phi2 + rAU1f*(g & mesh.Sf())
    );
    surfaceScalarField phiDrag2
    (
        fvc::interpolate(alpha1/rho2*dragCoef*rAU2)*phi1 + rAU2f*(g & mesh.Sf())
    );

    forAll(p.boundaryField(), patchi)
    {
        if (isA<zeroGradientFvPatchScalarField>(p.boundaryField()[patchi]))
        {
            phiDrag1.boundaryField()[patchi] = 0.0;
            phiDrag2.boundaryField()[patchi] = 0.0;
        }
    }

    phi1 = (fvc::interpolate(U1) & mesh.Sf()) + fvc::ddtPhiCorr(rAU1, U1, phi1)
        + phiDrag1;
    phi2 = (fvc::interpolate(U2) & mesh.Sf()) + fvc::ddtPhiCorr(rAU2, U2, phi2)
        + phiDrag2;

    phi = alpha1f*phi1 + alpha2f*phi2;

    surfaceScalarField Dp
    (
        "(rho*(1|A(U)))",
        alpha1f*rAU1f/rho1 + alpha2f*rAU2f/rho2
    );

    while (pimple.correctNonOrthogonal())
    {
        fvScalarMatrix pEqn
        (
            fvm::laplacian(Dp, p) == fvc::div(phi)
        );

        pEqn.setReference(pRefCell, pRefValue);

        pEqn.solve(mesh.solver(p.select(pimple.finalInnerIter())));

        if (pimple.finalNonOrthogonalIter())
        {
            surfaceScalarField SfGradp(pEqn.flux()/Dp);

            phi1 -= rAU1f*SfGradp/rho1;
            phi2 -= rAU2f*SfGradp/rho2;
            phi = alpha1f*phi1 + alpha2f*phi2;

            p.relax();
            SfGradp = pEqn.flux()/Dp;

            U1 += (fvc::reconstruct(phiDrag1 - rAU1f*SfGradp/rho1));
            //U1 += rAU1*(fvc::reconstruct(phiDrag1/rAU1f - SfGradp/rho1));
            U1.correctBoundaryConditions();

            U2 += (fvc::reconstruct(phiDrag2 - rAU2f*SfGradp/rho2));
            //U2 += rAU2*(fvc::reconstruct(phiDrag2/rAU2f - SfGradp/rho2));
            U2.correctBoundaryConditions();

            U = alpha1*U1 + alpha2*U2;
        }
    }
}

#include "continuityErrs.H"