viewFactor.C

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    Copyright (C) 2011-2016 OpenFOAM Foundation
    Copyright (C) 2016-2019 OpenCFD Ltd.
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License
    This file is part of OpenFOAM.
 
    OpenFOAM is free software: you can redistribute it and/or modify it
    under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
 
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    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    for more details.
 
    You should have received a copy of the GNU General Public License
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#include "viewFactor.H"
#include "surfaceFields.H"
#include "constants.H"
#include "greyDiffusiveViewFactorFixedValueFvPatchScalarField.H"
#include "typeInfo.H"
#include "addToRunTimeSelectionTable.H"
#include "boundaryRadiationProperties.H"
 
using namespace Foam::constant;
 
// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
namespace Foam
{
    namespace radiation
    {
        defineTypeNameAndDebug(viewFactor, 0);
        addToRadiationRunTimeSelectionTables(viewFactor);
    }
}
 
const Foam::word Foam::radiation::viewFactor::viewFactorWalls
    = "viewFactorWall";
 
// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
void Foam::radiation::viewFactor::initialise()
{
    const polyBoundaryMesh& coarsePatches = coarseMesh_.boundaryMesh();
 
    selectedPatches_ = mesh_.boundaryMesh().indices(viewFactorWalls);
 
    for (const label patchi : selectedPatches_)
    {
        nLocalCoarseFaces_ += coarsePatches[patchi].size();
    }
 
    if (debug)
    {
        Pout<< "radiation::viewFactor::initialise() Selected patches:"
            << selectedPatches_ << endl;
        Pout<< "radiation::viewFactor::initialise() Number of coarse faces:"
            << nLocalCoarseFaces_ << endl;
    }
 
    totalNCoarseFaces_ = nLocalCoarseFaces_;
    reduce(totalNCoarseFaces_, sumOp<label>());
 
    if (debug && Pstream::master())
    {
        InfoInFunction
            << "Total number of clusters : " << totalNCoarseFaces_ << endl;
    }
 
    map_.reset
    (
        new IOmapDistribute
        (
            IOobject
            (
                "mapDist",
                mesh_.facesInstance(),
                mesh_,
                IOobject::MUST_READ,
                IOobject::NO_WRITE,
                false
            )
        )
    );
 
    scalarListIOList FmyProc
    (
        IOobject
        (
            "F",
            mesh_.facesInstance(),
            mesh_,
            IOobject::MUST_READ,
            IOobject::NO_WRITE,
            false
        )
    );
 
    labelListIOList globalFaceFaces
    (
        IOobject
        (
            "globalFaceFaces",
            mesh_.facesInstance(),
            mesh_,
            IOobject::MUST_READ,
            IOobject::NO_WRITE,
            false
        )
    );
 
    List<labelListList> globalFaceFacesProc(Pstream::nProcs());
    globalFaceFacesProc[Pstream::myProcNo()] = globalFaceFaces;
    Pstream::gatherList(globalFaceFacesProc);
 
    List<scalarListList> F(Pstream::nProcs());
    F[Pstream::myProcNo()] = FmyProc;
    Pstream::gatherList(F);
 
    globalIndex globalNumbering(nLocalCoarseFaces_);
 
    if (Pstream::master())
    {
        Fmatrix_.reset
        (
            new scalarSquareMatrix(totalNCoarseFaces_, Zero)
        );
 
        if (debug)
        {
            InfoInFunction
                << "Insert elements in the matrix..." << endl;
        }
 
        for (label procI = 0; procI < Pstream::nProcs(); procI++)
        {
            insertMatrixElements
            (
                globalNumbering,
                procI,
                globalFaceFacesProc[procI],
                F[procI],
                Fmatrix_()
            );
        }
 
 
        if (coeffs_.get<bool>("smoothing"))
        {
            if (debug)
            {
                InfoInFunction
                    << "Smoothing the matrix..." << endl;
            }
 
            for (label i=0; i<totalNCoarseFaces_; i++)
            {
                scalar sumF = 0.0;
                for (label j=0; j<totalNCoarseFaces_; j++)
                {
                    sumF += Fmatrix_()(i, j);
                }
 
                const scalar delta = sumF - 1.0;
                for (label j=0; j<totalNCoarseFaces_; j++)
                {
                    Fmatrix_()(i, j) *= (1.0 - delta/(sumF + 0.001));
                }
            }
        }
 
        coeffs_.readEntry("constantEmissivity", constEmissivity_);
        if (constEmissivity_)
        {
            CLU_.reset
            (
                new scalarSquareMatrix(totalNCoarseFaces_, Zero)
            );
 
            pivotIndices_.setSize(CLU_().m());
        }
    }
 
    coeffs_.readIfPresent("useSolarLoad", useSolarLoad_);
 
    if (useSolarLoad_)
    {
        const dictionary& solarDict = this->subDict("solarLoadCoeffs");
        solarLoad_.reset(new solarLoad(solarDict, T_));
 
        if (solarLoad_->nBands() != nBands_)
        {
            FatalErrorInFunction
                << "Solar radiation and view factor band numbers "
                << "are different"
                << abort(FatalError);
        }
 
        Info<< "Creating Solar Load Model " << nl;
    }
}
 
 
// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
Foam::radiation::viewFactor::viewFactor(const volScalarField& T)
:
    radiationModel(typeName, T),
    finalAgglom_
    (
        IOobject
        (
            "finalAgglom",
            mesh_.facesInstance(),
            mesh_,
            IOobject::MUST_READ,
            IOobject::NO_WRITE,
            false
        )
    ),
    map_(),
    coarseMesh_
    (
        IOobject
        (
            "coarse:" + mesh_.name(),
            mesh_.polyMesh::instance(),
            mesh_.time(),
            IOobject::NO_READ,
            IOobject::NO_WRITE,
            false
        ),
        mesh_,
        finalAgglom_
    ),
    qr_
    (
        IOobject
        (
            "qr",
            mesh_.time().timeName(),
            mesh_,
            IOobject::MUST_READ,
            IOobject::AUTO_WRITE
        ),
        mesh_
    ),
    Fmatrix_(),
    CLU_(),
    selectedPatches_(mesh_.boundary().size(), -1),
    totalNCoarseFaces_(0),
    nLocalCoarseFaces_(0),
    constEmissivity_(false),
    iterCounter_(0),
    pivotIndices_(0),
    useSolarLoad_(false),
    solarLoad_(),
    nBands_(coeffs_.lookupOrDefault<label>("nBands", 1))
{
    initialise();
}
 
 
Foam::radiation::viewFactor::viewFactor
(
    const dictionary& dict,
    const volScalarField& T
)
:
    radiationModel(typeName, dict, T),
    finalAgglom_
    (
        IOobject
        (
            "finalAgglom",
            mesh_.facesInstance(),
            mesh_,
            IOobject::MUST_READ,
            IOobject::NO_WRITE,
            false
        )
    ),
    map_(),
    coarseMesh_
    (
        IOobject
        (
            "coarse:" + mesh_.name(),
            mesh_.polyMesh::instance(),
            mesh_.time(),
            IOobject::NO_READ,
            IOobject::NO_WRITE,
            false
        ),
        mesh_,
        finalAgglom_
    ),
    qr_
    (
        IOobject
        (
            "qr",
            mesh_.time().timeName(),
            mesh_,
            IOobject::MUST_READ,
            IOobject::AUTO_WRITE
        ),
        mesh_
    ),
    Fmatrix_(),
    CLU_(),
    selectedPatches_(mesh_.boundary().size(), -1),
    totalNCoarseFaces_(0),
    nLocalCoarseFaces_(0),
    constEmissivity_(false),
    iterCounter_(0),
    pivotIndices_(0),
    useSolarLoad_(false),
    solarLoad_(),
    nBands_(coeffs_.lookupOrDefault<label>("nBands", 1))
{
    initialise();
}
 
 
// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
bool Foam::radiation::viewFactor::read()
{
    if (radiationModel::read())
    {
        return true;
    }
 
    return false;
}
 
 
void Foam::radiation::viewFactor::insertMatrixElements
(
    const globalIndex& globalNumbering,
    const label procI,
    const labelListList& globalFaceFaces,
    const scalarListList& viewFactors,
    scalarSquareMatrix& Fmatrix
)
{
    forAll(viewFactors, faceI)
    {
        const scalarList& vf = viewFactors[faceI];
        const labelList& globalFaces = globalFaceFaces[faceI];
 
        label globalI = globalNumbering.toGlobal(procI, faceI);
        forAll(globalFaces, i)
        {
            Fmatrix[globalI][globalFaces[i]] = vf[i];
        }
    }
}
 
 
void Foam::radiation::viewFactor::calculate()
{
    // Store previous iteration
    qr_.storePrevIter();
 
    if (useSolarLoad_)
    {
        solarLoad_->calculate();
    }
 
     // Net radiation
    scalarField q(totalNCoarseFaces_, 0.0);
    volScalarField::Boundary& qrBf = qr_.boundaryFieldRef();
 
    globalIndex globalNumbering(nLocalCoarseFaces_);
 
    const boundaryRadiationProperties& boundaryRadiation =
        boundaryRadiationProperties::New(mesh_);
 
    for (label bandI = 0; bandI < nBands_; bandI++)
    {
        scalarField compactCoarseT4(map_->constructSize(), 0.0);
        scalarField compactCoarseE(map_->constructSize(), 0.0);
        scalarField compactCoarseHo(map_->constructSize(), 0.0);
 
        // Fill local averaged(T), emissivity(E) and external heatFlux(Ho)
        DynamicList<scalar> localCoarseT4ave(nLocalCoarseFaces_);
        DynamicList<scalar> localCoarseEave(nLocalCoarseFaces_);
        DynamicList<scalar> localCoarseHoave(nLocalCoarseFaces_);
 
        forAll(selectedPatches_, i)
        {
            label patchID = selectedPatches_[i];
 
            const scalarField& Tp = T_.boundaryField()[patchID];
            const scalarField& sf = mesh_.magSf().boundaryField()[patchID];
 
            fvPatchScalarField& qrPatch = qrBf[patchID];
 
            greyDiffusiveViewFactorFixedValueFvPatchScalarField& qrp =
                refCast
                <
                    greyDiffusiveViewFactorFixedValueFvPatchScalarField
                >(qrPatch);
 
            const tmp<scalarField> teb =
                boundaryRadiation.emissivity(patchID, bandI);
 
            const scalarField& eb = teb();
 
            const tmp<scalarField> tHoi = qrp.qro(bandI);
            const scalarField& Hoi = tHoi();
 
            const polyPatch& pp = coarseMesh_.boundaryMesh()[patchID];
 
            const labelList& coarsePatchFace =
                coarseMesh_.patchFaceMap()[patchID];
 
            scalarList T4ave(pp.size(), 0.0);
            scalarList Eave(pp.size(), 0.0);
            scalarList Hoiave(pp.size(), 0.0);
 
            if (pp.size() > 0)
            {
                const labelList& agglom = finalAgglom_[patchID];
                label nAgglom = max(agglom) + 1;
 
                labelListList coarseToFine(invertOneToMany(nAgglom, agglom));
 
                forAll(coarseToFine, coarseI)
                {
                    const label coarseFaceID = coarsePatchFace[coarseI];
                    const labelList& fineFaces = coarseToFine[coarseFaceID];
                    UIndirectList<scalar> fineSf
                    (
                        sf,
                        fineFaces
                    );
 
                    const scalar area = sum(fineSf());
 
                    // Temperature, emissivity and external flux area weighting
                    forAll(fineFaces, j)
                    {
                        label facei = fineFaces[j];
                        T4ave[coarseI] += (pow4(Tp[facei])*sf[facei])/area;
                        Eave[coarseI] += (eb[facei]*sf[facei])/area;
                        Hoiave[coarseI] += (Hoi[facei]*sf[facei])/area;
                    }
                }
            }
 
            localCoarseT4ave.append(T4ave);
            localCoarseEave.append(Eave);
            localCoarseHoave.append(Hoiave);
 
        }
 
        // Fill the local values to distribute
        SubList<scalar>(compactCoarseT4, nLocalCoarseFaces_) =
            localCoarseT4ave;
        SubList<scalar>(compactCoarseE, nLocalCoarseFaces_) = localCoarseEave;
        SubList<scalar>(compactCoarseHo, nLocalCoarseFaces_) =
            localCoarseHoave;
 
        // Distribute data
        map_->distribute(compactCoarseT4);
        map_->distribute(compactCoarseE);
        map_->distribute(compactCoarseHo);
 
        // Distribute local global ID
        labelList compactGlobalIds(map_->constructSize(), Zero);
 
        SubList<label>
        (
            compactGlobalIds,
            nLocalCoarseFaces_
        ) = identity
            (
                globalNumbering.localSize(),
                globalNumbering.localStart()
            );
 
        map_->distribute(compactGlobalIds);
 
        // Create global size vectors
        scalarField T4(totalNCoarseFaces_, 0.0);
        scalarField E(totalNCoarseFaces_, 0.0);
        scalarField qrExt(totalNCoarseFaces_, 0.0);
 
        // Fill lists from compact to global indexes.
        forAll(compactCoarseT4, i)
        {
            T4[compactGlobalIds[i]] = compactCoarseT4[i];
            E[compactGlobalIds[i]] = compactCoarseE[i];
            qrExt[compactGlobalIds[i]] = compactCoarseHo[i];
        }
 
        Pstream::listCombineGather(T4, maxEqOp<scalar>());
        Pstream::listCombineGather(E, maxEqOp<scalar>());
        Pstream::listCombineGather(qrExt, maxEqOp<scalar>());
 
        Pstream::listCombineScatter(T4);
        Pstream::listCombineScatter(E);
        Pstream::listCombineScatter(qrExt);
 
        if (Pstream::master())
        {
            // Variable emissivity
            if (!constEmissivity_)
            {
                scalarSquareMatrix C(totalNCoarseFaces_, 0.0);
 
                for (label i=0; i<totalNCoarseFaces_; i++)
                {
                    for (label j=0; j<totalNCoarseFaces_; j++)
                    {
                        const scalar invEj = 1.0/E[j];
                        const scalar sigmaT4 =
                            physicoChemical::sigma.value()*T4[j];
 
                        if (i==j)
                        {
                            C(i, j) = invEj - (invEj - 1.0)*Fmatrix_()(i, j);
                            q[i] +=
                                (Fmatrix_()(i, j) - 1.0)*sigmaT4 + qrExt[j];
                        }
                        else
                        {
                            C(i, j) = (1.0 - invEj)*Fmatrix_()(i, j);
                            q[i] += Fmatrix_()(i, j)*sigmaT4;
                        }
 
                    }
                }
 
                Info<< "Solving view factor equations for band :"
                    << bandI << endl;
 
                // Negative coming into the fluid
                LUsolve(C, q);
            }
            else //Constant emissivity
            {
                // Initial iter calculates CLU and caches it
                if (iterCounter_ == 0)
                {
                    for (label i=0; i<totalNCoarseFaces_; i++)
                    {
                        for (label j=0; j<totalNCoarseFaces_; j++)
                        {
                            const scalar invEj = 1.0/E[j];
                            if (i==j)
                            {
                                CLU_()(i, j) =
                                    invEj-(invEj-1.0)*Fmatrix_()(i, j);
                            }
                            else
                            {
                                CLU_()(i, j) = (1.0 - invEj)*Fmatrix_()(i, j);
                            }
                        }
                    }
 
                    if (debug)
                    {
                        InfoInFunction
                            << "\nDecomposing C matrix..." << endl;
                    }
 
                    LUDecompose(CLU_(), pivotIndices_);
                }
 
                for (label i=0; i<totalNCoarseFaces_; i++)
                {
                    for (label j=0; j<totalNCoarseFaces_; j++)
                    {
                        const scalar sigmaT4 =
                            constant::physicoChemical::sigma.value()*T4[j];
 
                        if (i==j)
                        {
                            q[i] +=
                            (Fmatrix_()(i, j) - 1.0)*sigmaT4  + qrExt[j];
                        }
                        else
                        {
                            q[i] += Fmatrix_()(i, j)*sigmaT4;
                        }
                    }
                }
 
 
                Info<< "Solving view factor equations for band : "
                    << bandI  << endl;
 
 
                LUBacksubstitute(CLU_(), pivotIndices_, q);
                iterCounter_ ++;
            }
        }
 
    }
    // Scatter q and fill qr
    Pstream::listCombineScatter(q);
    Pstream::listCombineGather(q, maxEqOp<scalar>());
 
    label globCoarseId = 0;
    for (const label patchID : selectedPatches_)
    {
        const polyPatch& pp = mesh_.boundaryMesh()[patchID];
 
        if (pp.size() > 0)
        {
            scalarField& qrp = qrBf[patchID];
            const scalarField& sf = mesh_.magSf().boundaryField()[patchID];
            const labelList& agglom = finalAgglom_[patchID];
            label nAgglom = max(agglom)+1;
 
            labelListList coarseToFine(invertOneToMany(nAgglom, agglom));
 
            const labelList& coarsePatchFace =
                coarseMesh_.patchFaceMap()[patchID];
 
            scalar heatFlux = 0.0;
            forAll(coarseToFine, coarseI)
            {
                label globalCoarse =
                    globalNumbering.toGlobal
                    (Pstream::myProcNo(), globCoarseId);
 
                const label coarseFaceID = coarsePatchFace[coarseI];
                const labelList& fineFaces = coarseToFine[coarseFaceID];
                forAll(fineFaces, k)
                {
                    label faceI = fineFaces[k];
 
                    qrp[faceI] = q[globalCoarse];
                    heatFlux += qrp[faceI]*sf[faceI];
                }
                globCoarseId ++;
            }
        }
    }
 
    if (debug)
    {
        forAll(qrBf, patchID)
        {
            const scalarField& qrp = qrBf[patchID];
            const scalarField& magSf = mesh_.magSf().boundaryField()[patchID];
            const scalar heatFlux = gSum(qrp*magSf);
 
            InfoInFunction
                << "Total heat transfer rate at patch: "
                << patchID << " "
                << heatFlux << endl;
        }
    }
 
    // Relax qr if necessary
    qr_.relax();
}
 
 
Foam::tmp<Foam::volScalarField> Foam::radiation::viewFactor::Rp() const
{
    return tmp<volScalarField>::New
    (
        IOobject
        (
            "Rp",
            mesh_.time().timeName(),
            mesh_,
            IOobject::NO_READ,
            IOobject::NO_WRITE,
            false
        ),
        mesh_,
        dimensionedScalar
        (
            dimMass/dimLength/pow3(dimTime)/pow4(dimTemperature), Zero
        )
    );
}
 
 
Foam::tmp<Foam::DimensionedField<Foam::scalar, Foam::volMesh>>
Foam::radiation::viewFactor::Ru() const
{
    return tmp<DimensionedField<scalar, volMesh>>::New
    (
        IOobject
        (
            "Ru",
            mesh_.time().timeName(),
            mesh_,
            IOobject::NO_READ,
            IOobject::NO_WRITE,
            false
        ),
        mesh_,
        dimensionedScalar(dimMass/dimLength/pow3(dimTime), Zero)
    );
}
 
 
// ************************************************************************* //