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DeardorffDiffStress.H

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00001 /*---------------------------------------------------------------------------*\
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00004    \\    /   O peration     |
00005     \\  /    A nd           | Copyright (C) 1991-2010 OpenCFD Ltd.
00006      \\/     M anipulation  |
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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
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00014     (at your option) any later version.
00015 
00016     OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
00017     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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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, see <http://www.gnu.org/licenses/>.
00023 
00024 Class
00025     Foam::incompressible::LESModels::DeardorffDiffStress
00026 
00027 Description
00028     Differential SGS Stress Equation Model for incompressible flows
00029 
00030     The DSEM uses a model version of the full balance equation for the SGS
00031     stress tensor to simulate the behaviour of B.
00032     Thus,
00033     @verbatim
00034         d/dt(B) + div(U*B) - div(nuSgs*grad(B))
00035         =
00036         P - c1*epsilon/k*B - 0.667*(1 - c1)*epsilon*I - c2*(P - 0.333*trP*I)
00037 
00038     where
00039 
00040         k = 0.5*tr(B),
00041         epsilon = ce*k^3/2/delta,
00042         epsilon/k = ce*k^1/2/delta
00043         P = -(B'L + L'B)
00044         nuSgs = ck*sqrt(k)*delta
00045         nuEff = nuSgs + nu
00046     @endverbatim
00047 
00048 SourceFiles
00049     DeardorffDiffStress.C
00050 
00051 \*---------------------------------------------------------------------------*/
00052 
00053 #ifndef DeardorffDiffStress_H
00054 #define DeardorffDiffStress_H
00055 
00056 #include <incompressibleLESModels/GenSGSStress.H>
00057 
00058 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
00059 
00060 namespace Foam
00061 {
00062 namespace incompressible
00063 {
00064 namespace LESModels
00065 {
00066 
00067 /*---------------------------------------------------------------------------*\
00068                            Class DeardorffDiffStress Declaration
00069 \*---------------------------------------------------------------------------*/
00070 
00071 class DeardorffDiffStress
00072 :
00073     public GenSGSStress
00074 {
00075     // Private data
00076 
00077         dimensionedScalar ck_;
00078         dimensionedScalar cm_;
00079 
00080 
00081     // Private Member Functions
00082 
00083         //- Update sub-grid scale fields
00084         void updateSubGridScaleFields(const volScalarField& K);
00085 
00086         // Disallow default bitwise copy construct and assignment
00087         DeardorffDiffStress(const DeardorffDiffStress&);
00088         DeardorffDiffStress& operator=(const DeardorffDiffStress&);
00089 
00090 
00091 public:
00092 
00093     //- Runtime type information
00094     TypeName("DeardorffDiffStress");
00095 
00096     // Constructors
00097 
00098         //- Construct from components
00099         DeardorffDiffStress
00100         (
00101             const volVectorField& U,
00102             const surfaceScalarField& phi,
00103             transportModel& transport
00104         );
00105 
00106 
00107     //- Destructor
00108     virtual ~DeardorffDiffStress()
00109     {}
00110 
00111 
00112     // Member Functions
00113 
00114         //- Return the effective diffusivity for B
00115         tmp<volScalarField> DBEff() const
00116         {
00117             return tmp<volScalarField>
00118             (
00119                 new volScalarField("DBEff", nuSgs_ + nu())
00120             );
00121         }
00122 
00123         //- Correct Eddy-Viscosity and related properties
00124         virtual void correct(const tmp<volTensorField>& gradU);
00125 
00126         //- Read LESProperties dictionary
00127         virtual bool read();
00128 };
00129 
00130 
00131 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
00132 
00133 } // End namespace LESModels
00134 } // End namespace incompressible
00135 } // End namespace Foam
00136 
00137 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
00138 
00139 #endif
00140 
00141 // ************************ vim: set sw=4 sts=4 et: ************************ //
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