openfoam/applications/solvers/incompressible/ajointShapeOptimizationFoam/adjointShapeOptimizationFoam.C

/*---------------------------------------------------------------------------*\
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    \\  /    A nd           | Copyright (C) 1991-2010 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 2 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
    along with OpenFOAM; if not, write to the Free Software Foundation,
    Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

Application
    ajointShapeOptimizationFoam

Description
    Steady-state solver for incompressible, turbulent flow of non-Newtonian
    fluids with optimisation of duct shape by applying "blockage" in regions
    causing pressure loss as estimated using an adjoint formulation.

    References:
    @verbatim
        "Implementation of a continuous adjoint for topology optimization of
         ducted flows"
        C. Othmer,
        E. de Villiers,
        H.G. Weller
        AIAA-2007-3947
        http://pdf.aiaa.org/preview/CDReadyMCFD07_1379/PV2007_3947.pdf
    @endverbatim

    Note that this solver optimises for total pressure loss whereas the
    above paper describes the method for optimising power-loss.

\*---------------------------------------------------------------------------*/

#include "fvCFD.H"
#include "singlePhaseTransportModel.H"
#include "RASModel.H"

template<class Type>
void zeroCells
(
    GeometricField<Type, fvPatchField, volMesh>& vf,
    const labelList& cells
)
{
    forAll(cells, i)
    {
        vf[cells[i]] = pTraits<Type>::zero;
    }
}


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

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

    #include "createTime.H"
    #include "createMesh.H"
    #include "createFields.H"
    #include "initContinuityErrs.H"

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

    Info<< "\nStarting time loop\n" << endl;

    for (runTime++; !runTime.end(); runTime++)
    {
        Info<< "Time = " << runTime.timeName() << nl << endl;

        #include "readSIMPLEControls.H"

        p.storePrevIter();

        laminarTransport.lookup("lambda") >> lambda;

        //alpha +=
        //    mesh.relaxationFactor("alpha")
        //   *(lambda*max(Ua & U, zeroSensitivity) - alpha);
        alpha +=
            mesh.relaxationFactor("alpha")
           *(min(max(alpha + lambda*(Ua & U), zeroAlpha), alphaMax) - alpha);

        zeroCells(alpha, inletCells);
        //zeroCells(alpha, outletCells);

        // Pressure-velocity SIMPLE corrector
        {
            // Momentum predictor

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

            UEqn().relax();

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

            p.boundaryField().updateCoeffs();
            volScalarField rAU = 1.0/UEqn().A();
            U = rAU*UEqn().H();
            UEqn.clear();
            phi = fvc::interpolate(U) & mesh.Sf();
            adjustPhi(phi, U, p);

            // Non-orthogonal pressure corrector loop
            for (int nonOrth=0; nonOrth<=nNonOrthCorr; nonOrth++)
            {
                fvScalarMatrix pEqn
                (
                    fvm::laplacian(rAU, p) == fvc::div(phi)
                );

                pEqn.setReference(pRefCell, pRefValue);
                pEqn.solve();

                if (nonOrth == nNonOrthCorr)
                {
                    phi -= pEqn.flux();
                }
            }

            #include "continuityErrs.H"

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

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

        pa.storePrevIter();

        // Adjoint Pressure-velocity SIMPLE corrector
        {
            // Adjoint Momentum predictor

            volVectorField adjointTransposeConvection = (fvc::grad(Ua) & U);
            //volVectorField adjointTransposeConvection = fvc::reconstruct
            //(
            //    mesh.magSf()*(fvc::snGrad(Ua) & fvc::interpolate(U))
            //);

            zeroCells(adjointTransposeConvection, inletCells);

            tmp<fvVectorMatrix> UaEqn
            (
                fvm::div(-phi, Ua)
              - adjointTransposeConvection
              + turbulence->divDevReff(Ua)
              + fvm::Sp(alpha, Ua)
            );

            UaEqn().relax();

            solve(UaEqn() == -fvc::grad(pa));

            pa.boundaryField().updateCoeffs();
            volScalarField rAUa = 1.0/UaEqn().A();
            Ua = rAUa*UaEqn().H();
            UaEqn.clear();
            phia = fvc::interpolate(Ua) & mesh.Sf();
            adjustPhi(phia, Ua, pa);

            // Non-orthogonal pressure corrector loop
            for (int nonOrth=0; nonOrth<=nNonOrthCorr; nonOrth++)
            {
                fvScalarMatrix paEqn
                (
                    fvm::laplacian(rAUa, pa) == fvc::div(phia)
                );

                paEqn.setReference(paRefCell, paRefValue);
                paEqn.solve();

                if (nonOrth == nNonOrthCorr)
                {
                    phia -= paEqn.flux();
                }
            }

            #include "adjointContinuityErrs.H"

            // Explicitly relax pressure for adjoint momentum corrector
            pa.relax();

            // Adjoint momentum corrector
            Ua -= rAUa*fvc::grad(pa);
            Ua.correctBoundaryConditions();
        }

        turbulence->correct();

        runTime.write();

        Info<< "ExecutionTime = "
            << runTime.elapsedCpuTime()
            << " s\n\n" << endl;
    }

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

    return(0);
}


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