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DeardorffDiffStress.H

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00001 /*---------------------------------------------------------------------------*\
00002   =========                 |
00003   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
00004    \\    /   O peration     |
00005     \\  /    A nd           | Copyright (C) 1991-2005 OpenCFD Ltd.
00006      \\/     M anipulation  |
00007 -------------------------------------------------------------------------------
00008 License
00009     This file is part of OpenFOAM.
00010 
00011     OpenFOAM is free software; you can redistribute it and/or modify it
00012     under the terms of the GNU General Public License as published by the
00013     Free Software Foundation; either version 2 of the License, or (at your
00014     option) any later version.
00015 
00016     OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
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00019     for more details.
00020 
00021     You should have received a copy of the GNU General Public License
00022     along with OpenFOAM; if not, write to the Free Software Foundation,
00023     Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
00024 
00025 Class
00026     DeardorffDiffStress
00027 
00028 Description
00029 <pre>
00030       Differential SGS Stress Equation Model
00031       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
00032       The DSEM uses a model version of the full balance equation for the SGS
00033       stress tensor to simulate the behaviour of B, hence,
00034 
00035           d/dt(B) + div(U*B) - div(nuSgs*grad(B))
00036           =
00037           P - c1*epsilon/k*B - 0.667*(1 - c1)*epsilon*I - c2*(P - 0.333*trP*I)
00038 
00039       where
00040 
00041           k = 0.5*tr(B),
00042           epsilon = ce*k^3/2/delta,
00043           epsilon/k = ce*k^1/2/delta
00044           P = -(B'L + L'B)
00045           nuSgs = ck*sqrt(k)*delta
00046           nuEff = nuSgs + nu
00047 </pre>
00048 
00049 SourceFiles
00050     DeardorffDiffStress.C
00051 
00052 \*---------------------------------------------------------------------------*/
00053 
00054 #ifndef DeardorffDiffStress_H
00055 #define DeardorffDiffStress_H
00056 
00057 #include "GenSGSStress.H"
00058 
00059 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
00060 
00061 namespace Foam
00062 {
00063 namespace LESmodels
00064 {
00065 
00066 /*---------------------------------------------------------------------------*\
00067                            Class DeardorffDiffStress Declaration
00068 \*---------------------------------------------------------------------------*/
00069 
00070 class DeardorffDiffStress
00071 :
00072     public GenSGSStress
00073 {
00074     // Private data
00075 
00076         dimensionedScalar ck_;
00077         dimensionedScalar cm_;
00078 
00079 
00080     // Private Member Functions
00081 
00082         // Disallow default bitwise copy construct and assignment
00083         DeardorffDiffStress(const DeardorffDiffStress&);
00084         DeardorffDiffStress& operator=(const DeardorffDiffStress&);
00085 
00086 
00087 public:
00088 
00089     //- Runtime type information
00090     TypeName("DeardorffDiffStress");
00091 
00092     // Constructors
00093 
00094         //- Constructor from components
00095         DeardorffDiffStress
00096         (
00097             const volVectorField& U,
00098             const surfaceScalarField& phi,
00099             transportModel& transport
00100         );
00101 
00102 
00103     // Destructor
00104 
00105         ~DeardorffDiffStress()
00106         {}
00107 
00108 
00109     // Member Functions
00110 
00111         //- Return the effective diffusivity for B
00112         tmp<volScalarField> DBEff() const
00113         {
00114             return tmp<volScalarField> 
00115             (
00116                 new volScalarField("DBEff", nuSgs_ + nu())
00117             );
00118         }
00119 
00120         //- Correct Eddy-Viscosity and related properties
00121         void correct(const tmp<volTensorField>& gradU);
00122 
00123         //- Read turbulenceProperties dictionary
00124         bool read();
00125 };
00126 
00127 
00128 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
00129 
00130 } // End namespace LESmodels
00131 } // End namespace Foam
00132 
00133 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
00134 
00135 #endif
00136 
00137 // ************************************************************************* //
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