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/* This file is part of the OpenLB library
*
* Copyright (C) 2012 Patrick Nathen, Mathias J. Krause
* E-mail contact: info@openlb.net
* The most recent release of OpenLB can be downloaded at
* <http://www.openlb.net/>
*
* This program 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 2
* of the License, or (at your option) any later version.
*
* This program 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 this program; if not, write to the Free
* Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/** \file
* MRT Dynamics with adjusted omega -- header file.
*/
#ifndef SMAGORINSKY_MRT_DYNAMICS_H
#define SMAGORINSKY_MRT_DYNAMICS_H
#include "mrtDynamics.h"
#include "core/cell.h"
namespace olb {
/// Implementation of the MRT collision step
template<typename T, typename DESCRIPTOR>
class SmagorinskyMRTdynamics : public MRTdynamics<T,DESCRIPTOR> {
public:
/// Constructor
SmagorinskyMRTdynamics(T omega_, Momenta<T,DESCRIPTOR>& momenta_, T smagoConst_, T dx_ = 1, T dt_ = 1);
// Collide
virtual void collide(Cell<T,DESCRIPTOR>& cell,
LatticeStatistics<T>& statistics_);
/// Set local relaxation parameter of the dynamics
virtual void setOmega(T omega_);
/// Get local smagorinsky relaxation parameter of the dynamics
virtual T getSmagorinskyOmega(Cell<T,DESCRIPTOR>& cell_);
private:
/// Computes a constant prefactor in order to speed up the computation
T computePreFactor(T omega_, T smagoConst_);
/// Computes the local smagorinsky relaxation parameter
T computeOmega(T omega0_, T preFactor_, T rho_, T pi_[util::TensorVal<DESCRIPTOR >::n] );
protected:
/// Smagorinsky constant
T smagoConst;
/// Precomputed constant which speeeds up the computation
T preFactor;
T omega; // the shear viscosity relaxatin time
T lambda;// the bulk viscosity relaxatin time
/// effective collision time based upon Smagorisnky approach
T tau_eff;
T dx;
T dt;
// Relaxation Time Matrix for
T invM_S_SGS[DESCRIPTOR::q][DESCRIPTOR::q];
};
/// Implementation of the MRT collision step
template<typename T, typename DESCRIPTOR>
class SmagorinskyForcedMRTdynamics : public SmagorinskyMRTdynamics<T,DESCRIPTOR> {
public:
/// Constructor
SmagorinskyForcedMRTdynamics(T omega_, Momenta<T,DESCRIPTOR>& momenta_, T smagoConst_, T dx_, T dt_ ) : SmagorinskyMRTdynamics<T,DESCRIPTOR>(omega_, momenta_, smagoConst_, dx_, dt_ ) {};
// Collide
virtual void collide(Cell<T,DESCRIPTOR>& cell,
LatticeStatistics<T>& statistics_);
};
}
#endif
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