src/turbulenceModels/incompressible/LES/spectEddyVisc/spectEddyVisc.C

   1 /*---------------------------------------------------------------------------*\
   2   =========                 |
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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 the
  13     Free Software Foundation; either version 2 of the License, or (at your
  14     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, write to the Free Software Foundation,
  23     Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  24
  25 \*---------------------------------------------------------------------------*/
  26
  27 #include "spectEddyVisc.H"
  28 #include "addToRunTimeSelectionTable.H"
  29
  30 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
  31
  32 namespace Foam
  33 {
  34 namespace incompressible
  35 {
  36 namespace LESModels
  37 {
  38
  39 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
  40
  41 defineTypeNameAndDebug(spectEddyVisc, 0);
  42 addToRunTimeSelectionTable(LESModel, spectEddyVisc, dictionary);
  43
  44 // * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
  45
  46 void spectEddyVisc::updateSubGridScaleFields(const volTensorField& gradU)
  47 {
  48     volScalarField Re = sqr(delta())*mag(symm(gradU))/nu();
  49     for (label i=0; i<5; i++)
  50     {
  51         nuSgs_ =
  52             nu()
  53            /(
  54                  scalar(1)
  55                - exp(-cB_*pow(nu()/(nuSgs_ + nu()), 1.0/3.0)*pow(Re, -2.0/3.0))
  56             );
  57     }
  58
  59     nuSgs_.correctBoundaryConditions();
  60 }
  61
  62
  63 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
  64
  65 spectEddyVisc::spectEddyVisc
  66 (
  67     const volVectorField& U,
  68     const surfaceScalarField& phi,
  69     transportModel& transport
  70 )
  71 :
  72     LESModel(typeName, U, phi, transport),
  73     GenEddyVisc(U, phi, transport),
  74
  75
  76     cB_
  77     (
  78         dimensioned<scalar>::lookupOrAddToDict
  79         (
  80             "cB",
  81             coeffDict_,
  82             8.22
  83         )
  84     ),
  85     cK1_
  86     (
  87         dimensioned<scalar>::lookupOrAddToDict
  88         (
  89             "cK1",
  90             coeffDict_,
  91             0.83
  92         )
  93     ),
  94     cK2_
  95     (
  96         dimensioned<scalar>::lookupOrAddToDict
  97         (
  98             "cK2",
  99             coeffDict_,
 100             1.03
 101         )
 102     ),
 103     cK3_
 104     (
 105         dimensioned<scalar>::lookupOrAddToDict
 106         (
 107             "cK3",
 108             coeffDict_,
 109             4.75
 110         )
 111     ),
 112     cK4_
 113     (
 114         dimensioned<scalar>::lookupOrAddToDict
 115         (
 116             "cK4",
 117             coeffDict_,
 118             2.55
 119         )
 120     )
 121 {
 122     printCoeffs();
 123
 124     updateSubGridScaleFields(fvc::grad(U));
 125 }
 126
 127
 128 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 129
 130 tmp<volScalarField> spectEddyVisc::k() const
 131 {
 132     volScalarField eps = 2*nuEff()*magSqr(symm(fvc::grad(U())));
 133
 134     return
 135         cK1_*pow(delta()*eps, 2.0/3.0)
 136        *exp(-cK2_*pow(delta(), -4.0/3.0)*nu()/pow(eps, 1.0/3.0))
 137       - cK3_*sqrt(eps*nu())
 138        *erfc(cK4_*pow(delta(), -2.0/3.0)*sqrt(nu())*pow(eps, -1.0/6.0));
 139 }
 140
 141
 142 void spectEddyVisc::correct(const tmp<volTensorField>& gradU)
 143 {
 144     GenEddyVisc::correct(gradU);
 145     updateSubGridScaleFields(gradU());
 146 }
 147
 148
 149 bool spectEddyVisc::read()
 150 {
 151     if (GenEddyVisc::read())
 152     {
 153         cB_.readIfPresent(coeffDict());
 154         cK1_.readIfPresent(coeffDict());
 155         cK2_.readIfPresent(coeffDict());
 156         cK3_.readIfPresent(coeffDict());
 157         cK4_.readIfPresent(coeffDict());
 158
 159         return true;
 160     }
 161     else
 162     {
 163         return false;
 164     }
 165 }
 166
 167
 168 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 169
 170 } // End namespace LESModels
 171 } // End namespace incompressible
 172 } // End namespace Foam
 173
 174 // ************************************************************************* //