src/regionModels/surfaceFilmModels/submodels/kinematic/force/contactAngleForce/contactAngleForce.C

   1 /*---------------------------------------------------------------------------*\
   2   =========                 |
   3   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   4    \\    /   O peration     |
   5     \\  /    A nd           | Copyright (C) 2011-2011 OpenCFD Ltd.
   6      \\/     M anipulation  |
   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 "contactAngleForce.H"
  27 #include "addToRunTimeSelectionTable.H"
  28 #include "fvcGrad.H"
  29 #include "unitConversion.H"
  30 #include "fvPatchField.H"
  31
  32 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
  33
  34 namespace Foam
  35 {
  36 namespace regionModels
  37 {
  38 namespace surfaceFilmModels
  39 {
  40
  41 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
  42
  43 defineTypeNameAndDebug(contactAngleForce, 0);
  44 addToRunTimeSelectionTable(force, contactAngleForce, dictionary);
  45
  46 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
  47
  48 contactAngleForce::contactAngleForce
  49 (
  50     const surfaceFilmModel& owner,
  51     const dictionary& dict
  52 )
  53 :
  54     force(typeName, owner, dict),
  55     deltaWet_(readScalar(coeffs_.lookup("deltaWet"))),
  56     Ccf_(readScalar(coeffs_.lookup("Ccf"))),
  57     rndGen_(label(0), -1),
  58     distribution_
  59     (
  60         distributionModels::distributionModel::New
  61         (
  62             coeffs_.subDict("contactAngleDistribution"),
  63             rndGen_
  64         )
  65     )
  66 {}
  67
  68
  69 // * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
  70
  71 contactAngleForce::~contactAngleForce()
  72 {}
  73
  74
  75 // * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //
  76
  77 tmp<fvVectorMatrix> contactAngleForce::correct(volVectorField& U)
  78 {
  79     tmp<volVectorField> tForce
  80     (
  81         new volVectorField
  82         (
  83             IOobject
  84             (
  85                 "contactForce",
  86                 owner_.time().timeName(),
  87                 owner_.regionMesh(),
  88                 IOobject::NO_READ,
  89                 IOobject::NO_WRITE
  90             ),
  91             owner_.regionMesh(),
  92             dimensionedVector("zero", dimForce/dimArea, vector::zero)
  93         )
  94     );
  95
  96     vectorField& force = tForce().internalField();
  97
  98     const labelUList& own = owner_.regionMesh().owner();
  99     const labelUList& nbr = owner_.regionMesh().neighbour();
 100
 101     const scalarField& magSf = owner_.magSf();
 102
 103     const volScalarField& delta = owner_.delta();
 104     const volScalarField& sigma = owner_.sigma();
 105
 106     volScalarField alpha
 107     (
 108         "alpha",
 109         pos(delta - dimensionedScalar("deltaWet", dimLength, deltaWet_))
 110     );
 111     volVectorField gradAlpha(fvc::grad(alpha));
 112
 113
 114     scalarField nHits(owner_.regionMesh().nCells(), 0.0);
 115
 116     forAll(nbr, faceI)
 117     {
 118         const label cellO = own[faceI];
 119         const label cellN = nbr[faceI];
 120
 121         label cellI = -1;
 122         if ((delta[cellO] > deltaWet_) && (delta[cellN] < deltaWet_))
 123         {
 124             cellI = cellO;
 125         }
 126         else if ((delta[cellO] < deltaWet_) && (delta[cellN] > deltaWet_))
 127         {
 128             cellI = cellN;
 129         }
 130
 131         if (cellI != -1)
 132         {
 133 //            const scalar dx = Foam::sqrt(magSf[cellI]);
 134             // bit of a cheat, but ok for regular meshes
 135             const scalar dx = owner_.regionMesh().deltaCoeffs()[faceI];
 136             const vector n =
 137                 gradAlpha[cellI]/(mag(gradAlpha[cellI]) + ROOTVSMALL);
 138             scalar theta = cos(degToRad(distribution_->sample()));
 139             force[cellI] += Ccf_*n*sigma[cellI]*(1.0 - theta)/dx;
 140             nHits[cellI]++;
 141         }
 142     }
 143
 144     forAll(delta.boundaryField(), patchI)
 145     {
 146         const fvPatchField<scalar>& df = delta.boundaryField()[patchI];
 147         const scalarField& dx = df.patch().deltaCoeffs();
 148         const labelUList& faceCells = df.patch().faceCells();
 149
 150         forAll(df, faceI)
 151         {
 152             label cellO = faceCells[faceI];
 153
 154             if ((delta[cellO] > deltaWet_) && (df[faceI] < deltaWet_))
 155             {
 156                 const vector n =
 157                     gradAlpha[cellO]/(mag(gradAlpha[cellO]) + ROOTVSMALL);
 158                 scalar theta = cos(degToRad(distribution_->sample()));
 159                 force[cellO] += Ccf_*n*sigma[cellO]*(1.0 - theta)/dx[faceI];
 160                 nHits[cellO]++;
 161             }
 162         }
 163     }
 164
 165     force /= (max(nHits, scalar(1.0))*magSf);
 166     tForce().correctBoundaryConditions();
 167
 168     if (owner_.regionMesh().time().outputTime())
 169     {
 170         tForce().write();
 171     }
 172
 173     tmp<fvVectorMatrix>
 174         tfvm(new fvVectorMatrix(U, dimForce/dimArea*dimVolume));
 175
 176     tfvm() += tForce;
 177
 178     return tfvm;
 179 }
 180
 181
 182 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 183
 184 } // End namespace surfaceFilmModels
 185 } // End namespace regionModels
 186 } // End namespace Foam
 187
 188 // ************************************************************************* //