168 lines
4.9 KiB
C++
168 lines
4.9 KiB
C++
/*---------------------------------------------------------------------------*\
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========= |
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\\ / F ield | foam-extend: Open Source CFD
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\\ / O peration | Version: 4.1
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\\ / A nd | Web: http://www.foam-extend.org
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\\/ M anipulation | For copyright notice see file Copyright
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-------------------------------------------------------------------------------
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License
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This file is part of foam-extend.
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foam-extend is free software: you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published by the
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Free Software Foundation, either version 3 of the License, or (at your
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option) any later version.
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foam-extend is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with foam-extend. If not, see <http://www.gnu.org/licenses/>.
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Application
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mhdFoam
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Description
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Solver for magnetohydrodynamics (MHD): incompressible, laminar flow of a
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conducting fluid under the influence of a magnetic field.
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An applied magnetic field H acts as a driving force,
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at present boundary conditions cannot be set via the
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electric field E or current density J. The fluid viscosity nu,
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conductivity sigma and permeability mu are read in as uniform
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constants.
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A fictitous magnetic flux pressure pH is introduced in order to
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compensate for discretisation errors and create a magnetic face flux
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field which is divergence free as required by Maxwell's equations.
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However, in this formulation discretisation error prevents the normal
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stresses in UB from cancelling with those from BU, but it is unknown
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whether this is a serious error. A correction could be introduced
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whereby the normal stresses in the discretised BU term are replaced
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by those from the UB term, but this would violate the boundedness
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constraint presently observed in the present numerics which
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guarantees div(U) and div(H) are zero.
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\*---------------------------------------------------------------------------*/
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#include "fvCFD.H"
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#include "OSspecific.H"
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#include "pisoControl.H"
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// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
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int main(int argc, char *argv[])
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{
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# include "setRootCase.H"
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# include "createTime.H"
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# include "createMesh.H"
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pisoControl piso(mesh);
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# include "createFields.H"
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# include "initContinuityErrs.H"
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// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
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Info<< nl << "Starting time loop" << endl;
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while (runTime.loop())
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{
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# include "readBPISOControls.H"
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Info<< "Time = " << runTime.timeName() << nl << endl;
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# include "CourantNo.H"
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{
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fvVectorMatrix UEqn
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(
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fvm::ddt(U)
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+ fvm::div(phi, U)
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- fvc::div(phiB, 2.0*DBU*B)
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- fvm::laplacian(nu, U)
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+ fvc::grad(DBU*magSqr(B))
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);
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solve(UEqn == -fvc::grad(p));
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// --- PISO loop
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while (piso.correct())
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{
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volScalarField rUA = 1.0/UEqn.A();
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U = rUA*UEqn.H();
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phi = (fvc::interpolate(U) & mesh.Sf())
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+ fvc::ddtPhiCorr(rUA, U, phi);
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while (piso.correctNonOrthogonal())
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{
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fvScalarMatrix pEqn
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(
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fvm::laplacian(rUA, p) == fvc::div(phi)
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);
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pEqn.setReference(pRefCell, pRefValue);
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pEqn.solve();
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if (piso.finalNonOrthogonalIter())
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{
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phi -= pEqn.flux();
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}
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}
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# include "continuityErrs.H"
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U -= rUA*fvc::grad(p);
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U.correctBoundaryConditions();
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}
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}
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// --- B-PISO loop
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for (int Bcorr=0; Bcorr<nBcorr; Bcorr++)
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{
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fvVectorMatrix BEqn
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(
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fvm::ddt(B)
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+ fvm::div(phi, B)
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- fvc::div(phiB, U)
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- fvm::laplacian(DB, B)
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);
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BEqn.solve();
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volScalarField rBA = 1.0/BEqn.A();
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phiB = (fvc::interpolate(B) & mesh.Sf())
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+ fvc::ddtPhiCorr(rBA, B, phiB);
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fvScalarMatrix pBEqn
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(
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fvm::laplacian(rBA, pB) == fvc::div(phiB)
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);
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pBEqn.solve();
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phiB -= pBEqn.flux();
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# include "magneticFieldErr.H"
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}
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runTime.write();
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}
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Info<< "End\n" << endl;
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return 0;
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}
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// ************************************************************************* //
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