View Issue Details
ID | Project | Category | View Status | Date Submitted | Last Update |
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0003036 | OpenFOAM | Feature | public | 2018-08-09 19:18 | 2018-08-09 23:08 |
Reporter | atulkjoy | Assigned To | henry | ||
Priority | normal | Severity | minor | Reproducibility | sometimes |
Status | closed | Resolution | no change required | ||
Platform | Linux | OS | CentOS | OS Version | 7.0 |
Product Version | dev | ||||
Summary | 0003036: Turbulence Model correction for RANS | ||||
Description | In my version of OpenFoam I have seen following lines 134 C3_ ( dimensioned<scalar>::lookupOrAddToDict ( "C3", this->coeffDict_, -0.33 ) ), 142 and In epsilon matrix fvm::SuSp(((2.0/3.0)*C1_ + C3_)*alpha()*rho()*divU, epsilon_) I guess default value of RDT coefficient C3 should be 0 also Transport term should be following fvm::SuSp(((2.0/3.0)*C1_ - C3_)*alpha()*rho()*divU, epsilon_) If issue is been noticed and corrected please notify | ||||
Steps To Reproduce | changing Lines 136 to 142 as C3_ ( dimensioned<scalar>::lookupOrAddToDict ( "C3", this->coeffDict_, 0 ) ), changing Transport equation for epsilon as fvm::SuSp(((2.0/3.0)*C1_ - C3_)*alpha()*rho()*divU, epsilon_) | ||||
Tags | No tags attached. | ||||
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The default C3 should be -0.33, if you want to run with 0 simply put it in your input dictionary for the model. What is the difference between fvm::SuSp(((2.0/3.0)*C1_ - C3_)*alpha()*rho()*divU, epsilon_) and fvm::SuSp(((2.0/3.0)*C1_ - C3_)*alpha()*rho()*divU, epsilon_) |
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kEpsilon.C (7,470 bytes)
/*---------------------------------------------------------------------------*\ ========= | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox \\ / O peration | \\ / A nd | Copyright (C) 2011-2016 OpenFOAM Foundation \\/ M anipulation | ------------------------------------------------------------------------------- License This file is part of OpenFOAM. OpenFOAM is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. OpenFOAM is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenFOAM. If not, see <http://www.gnu.org/licenses/>. \*---------------------------------------------------------------------------*/ #include "kEpsilon.H" #include "fvOptions.H" #include "bound.H" // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // namespace Foam { namespace RASModels { // * * * * * * * * * * * * Protected Member Functions * * * * * * * * * * * // template<class BasicTurbulenceModel> void kEpsilon<BasicTurbulenceModel>::correctNut() { this->nut_ = Cmu_*sqr(k_)/epsilon_; this->nut_.correctBoundaryConditions(); fv::options::New(this->mesh_).correct(this->nut_); BasicTurbulenceModel::correctNut(); } template<class BasicTurbulenceModel> tmp<fvScalarMatrix> kEpsilon<BasicTurbulenceModel>::kSource() const { return tmp<fvScalarMatrix> ( new fvScalarMatrix ( k_, dimVolume*this->rho_.dimensions()*k_.dimensions() /dimTime ) ); } template<class BasicTurbulenceModel> tmp<fvScalarMatrix> kEpsilon<BasicTurbulenceModel>::epsilonSource() const { return tmp<fvScalarMatrix> ( new fvScalarMatrix ( epsilon_, dimVolume*this->rho_.dimensions()*epsilon_.dimensions() /dimTime ) ); } // * * * * * * * * * * * * * * * * Constructors * * * * * * * * * * * * * * // template<class BasicTurbulenceModel> kEpsilon<BasicTurbulenceModel>::kEpsilon ( const alphaField& alpha, const rhoField& rho, const volVectorField& U, const surfaceScalarField& alphaRhoPhi, const surfaceScalarField& phi, const transportModel& transport, const word& propertiesName, const word& type ) : eddyViscosity<RASModel<BasicTurbulenceModel>> ( type, alpha, rho, U, alphaRhoPhi, phi, transport, propertiesName ), Cmu_ ( dimensioned<scalar>::lookupOrAddToDict ( "Cmu", this->coeffDict_, 0.09 ) ), C1_ ( dimensioned<scalar>::lookupOrAddToDict ( "C1", this->coeffDict_, 1.44 ) ), C2_ ( dimensioned<scalar>::lookupOrAddToDict ( "C2", this->coeffDict_, 1.92 ) ), C3_ ( dimensioned<scalar>::lookupOrAddToDict ( "C3", this->coeffDict_, -0.33 ) ), sigmak_ ( dimensioned<scalar>::lookupOrAddToDict ( "sigmak", this->coeffDict_, 1.0 ) ), sigmaEps_ ( dimensioned<scalar>::lookupOrAddToDict ( "sigmaEps", this->coeffDict_, 1.3 ) ), k_ ( IOobject ( IOobject::groupName("k", U.group()), this->runTime_.timeName(), this->mesh_, IOobject::MUST_READ, IOobject::AUTO_WRITE ), this->mesh_ ), epsilon_ ( IOobject ( IOobject::groupName("epsilon", U.group()), this->runTime_.timeName(), this->mesh_, IOobject::MUST_READ, IOobject::AUTO_WRITE ), this->mesh_ ) { bound(k_, this->kMin_); bound(epsilon_, this->epsilonMin_); if (type == typeName) { this->printCoeffs(type); } } // * * * * * * * * * * * * * * * Member Functions * * * * * * * * * * * * * // template<class BasicTurbulenceModel> bool kEpsilon<BasicTurbulenceModel>::read() { if (eddyViscosity<RASModel<BasicTurbulenceModel>>::read()) { Cmu_.readIfPresent(this->coeffDict()); C1_.readIfPresent(this->coeffDict()); C2_.readIfPresent(this->coeffDict()); C3_.readIfPresent(this->coeffDict()); sigmak_.readIfPresent(this->coeffDict()); sigmaEps_.readIfPresent(this->coeffDict()); return true; } else { return false; } } template<class BasicTurbulenceModel> void kEpsilon<BasicTurbulenceModel>::correct() { if (!this->turbulence_) { return; } // Local references const alphaField& alpha = this->alpha_; const rhoField& rho = this->rho_; const surfaceScalarField& alphaRhoPhi = this->alphaRhoPhi_; const volVectorField& U = this->U_; volScalarField& nut = this->nut_; fv::options& fvOptions(fv::options::New(this->mesh_)); eddyViscosity<RASModel<BasicTurbulenceModel>>::correct(); volScalarField::Internal divU ( fvc::div(fvc::absolute(this->phi(), U))().v() ); tmp<volTensorField> tgradU = fvc::grad(U); volScalarField::Internal G ( this->GName(), nut.v()*(dev(twoSymm(tgradU().v())) && tgradU().v()) ); tgradU.clear(); // Update epsilon and G at the wall epsilon_.boundaryFieldRef().updateCoeffs(); // Dissipation equation tmp<fvScalarMatrix> epsEqn ( fvm::ddt(alpha, rho, epsilon_) + fvm::div(alphaRhoPhi, epsilon_) - fvm::laplacian(alpha*rho*DepsilonEff(), epsilon_) == C1_*alpha()*rho()*G*epsilon_()/k_() - fvm::SuSp(((2.0/3.0)*C1_ + C3_)*alpha()*rho()*divU, epsilon_) - fvm::Sp(C2_*alpha()*rho()*epsilon_()/k_(), epsilon_) + epsilonSource() + fvOptions(alpha, rho, epsilon_) ); epsEqn.ref().relax(); fvOptions.constrain(epsEqn.ref()); epsEqn.ref().boundaryManipulate(epsilon_.boundaryFieldRef()); solve(epsEqn); fvOptions.correct(epsilon_); bound(epsilon_, this->epsilonMin_); // Turbulent kinetic energy equation tmp<fvScalarMatrix> kEqn ( fvm::ddt(alpha, rho, k_) + fvm::div(alphaRhoPhi, k_) - fvm::laplacian(alpha*rho*DkEff(), k_) == alpha()*rho()*G - fvm::SuSp((2.0/3.0)*alpha()*rho()*divU, k_) - fvm::Sp(alpha()*rho()*epsilon_()/k_(), k_) + kSource() + fvOptions(alpha, rho, k_) ); kEqn.ref().relax(); fvOptions.constrain(kEqn.ref()); solve(kEqn); fvOptions.correct(k_); bound(k_, this->kMin_); correctNut(); } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // } // End namespace RASModels } // End namespace Foam // ************************************************************************* // |
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I don't see the problem with this statement or the difference between it and the apparently identical form you provided. What exactly is the problem and what do you want changed to what and why? |
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It is not clear what changed is being proposed in this report. |
Date Modified | Username | Field | Change |
---|---|---|---|
2018-08-09 19:18 | atulkjoy | New Issue | |
2018-08-09 19:25 | henry | Note Added: 0009938 | |
2018-08-09 19:48 | atulkjoy | File Added: kEpsilon.C | |
2018-08-09 19:58 | henry | Note Added: 0009940 | |
2018-08-09 22:10 | henry | Assigned To | => henry |
2018-08-09 22:10 | henry | Status | new => closed |
2018-08-09 22:10 | henry | Resolution | open => no change required |
2018-08-09 22:10 | henry | Note Added: 0009943 |