src/OpenFOAM/matrices/lduMatrix/solvers/PCG/PCG.C

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   2   =========                 |
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   5     \\  /    A nd           | Copyright (C) 2011 OpenFOAM Foundation
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   7 -------------------------------------------------------------------------------
   8 License
   9     This file is part of OpenFOAM.
  10
  11     OpenFOAM is free software: you can redistribute it and/or modify it
  12     under the terms of the GNU General Public License as published by
  13     the Free Software Foundation, either version 3 of the License, or
  14     (at your option) any later version.
  15
  16     OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
  17     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  18     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  19     for more details.
  20
  21     You should have received a copy of the GNU General Public License
  22     along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 \*---------------------------------------------------------------------------*/
  25
  26 #include "PCG.H"
  27
  28 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
  29
  30 namespace Foam
  31 {
  32     defineTypeNameAndDebug(PCG, 0);
  33
  34     lduMatrix::solver::addsymMatrixConstructorToTable<PCG>
  35         addPCGSymMatrixConstructorToTable_;
  36 }
  37
  38
  39 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
  40
  41 Foam::PCG::PCG
  42 (
  43     const word& fieldName,
  44     const lduMatrix& matrix,
  45     const FieldField<Field, scalar>& interfaceBouCoeffs,
  46     const FieldField<Field, scalar>& interfaceIntCoeffs,
  47     const lduInterfaceFieldPtrsList& interfaces,
  48     const dictionary& solverControls
  49 )
  50 :
  51     lduMatrix::solver
  52     (
  53         fieldName,
  54         matrix,
  55         interfaceBouCoeffs,
  56         interfaceIntCoeffs,
  57         interfaces,
  58         solverControls
  59     )
  60 {}
  61
  62
  63 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
  64
  65 Foam::lduMatrix::solverPerformance Foam::PCG::solve
  66 (
  67     scalarField& psi,
  68     const scalarField& source,
  69     const direction cmpt
  70 ) const
  71 {
  72     // --- Setup class containing solver performance data
  73     lduMatrix::solverPerformance solverPerf
  74     (
  75         lduMatrix::preconditioner::getName(controlDict_) + typeName,
  76         fieldName_
  77     );
  78
  79     register label nCells = psi.size();
  80
  81     scalar* __restrict__ psiPtr = psi.begin();
  82
  83     scalarField pA(nCells);
  84     scalar* __restrict__ pAPtr = pA.begin();
  85
  86     scalarField wA(nCells);
  87     scalar* __restrict__ wAPtr = wA.begin();
  88
  89     scalar wArA = matrix_.great_;
  90     scalar wArAold = wArA;
  91
  92     // --- Calculate A.psi
  93     matrix_.Amul(wA, psi, interfaceBouCoeffs_, interfaces_, cmpt);
  94
  95     // --- Calculate initial residual field
  96     scalarField rA(source - wA);
  97     scalar* __restrict__ rAPtr = rA.begin();
  98
  99     // --- Calculate normalisation factor
 100     scalar normFactor = this->normFactor(psi, source, wA, pA);
 101
 102     if (lduMatrix::debug >= 2)
 103     {
 104         Info<< "   Normalisation factor = " << normFactor << endl;
 105     }
 106
 107     // --- Calculate normalised residual norm
 108     solverPerf.initialResidual() = gSumMag(rA)/normFactor;
 109     solverPerf.finalResidual() = solverPerf.initialResidual();
 110
 111     // --- Check convergence, solve if not converged
 112     if (!solverPerf.checkConvergence(tolerance_, relTol_))
 113     {
 114         // --- Select and construct the preconditioner
 115         autoPtr<lduMatrix::preconditioner> preconPtr =
 116         lduMatrix::preconditioner::New
 117         (
 118             *this,
 119             controlDict_
 120         );
 121
 122         // --- Solver iteration
 123         do
 124         {
 125             // --- Store previous wArA
 126             wArAold = wArA;
 127
 128             // --- Precondition residual
 129             preconPtr->precondition(wA, rA, cmpt);
 130
 131             // --- Update search directions:
 132             wArA = gSumProd(wA, rA);
 133
 134             if (solverPerf.nIterations() == 0)
 135             {
 136                 for (register label cell=0; cell<nCells; cell++)
 137                 {
 138                     pAPtr[cell] = wAPtr[cell];
 139                 }
 140             }
 141             else
 142             {
 143                 scalar beta = wArA/wArAold;
 144
 145                 for (register label cell=0; cell<nCells; cell++)
 146                 {
 147                     pAPtr[cell] = wAPtr[cell] + beta*pAPtr[cell];
 148                 }
 149             }
 150
 151
 152             // --- Update preconditioned residual
 153             matrix_.Amul(wA, pA, interfaceBouCoeffs_, interfaces_, cmpt);
 154
 155             scalar wApA = gSumProd(wA, pA);
 156
 157
 158             // --- Test for singularity
 159             if (solverPerf.checkSingularity(mag(wApA)/normFactor)) break;
 160
 161
 162             // --- Update solution and residual:
 163
 164             scalar alpha = wArA/wApA;
 165
 166             for (register label cell=0; cell<nCells; cell++)
 167             {
 168                 psiPtr[cell] += alpha*pAPtr[cell];
 169                 rAPtr[cell] -= alpha*wAPtr[cell];
 170             }
 171
 172             solverPerf.finalResidual() = gSumMag(rA)/normFactor;
 173
 174         } while
 175         (
 176             solverPerf.nIterations()++ < maxIter_
 177         && !(solverPerf.checkConvergence(tolerance_, relTol_))
 178         );
 179     }
 180
 181     return solverPerf;
 182 }
 183
 184
 185 // ************************************************************************* //