momentaonboundaries.h

open lattice boltzmann project www.openlb.org

/*  This file is part of the OpenLB library
 *
 *  Copyright (C) 2006, 2007 Jonas Latt
 *  Address: Rue General Dufour 24,  1211 Geneva 4, Switzerland 
 *  E-mail: [e-mail]
 *
 *  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
 * Implementation of boundary cell dynamics -- header file.
 */
#ifndef MOMENTA_ON_BOUNDARIES_H
#define MOMENTA_ON_BOUNDARIES_H

#include "dynamics.h"
#include "util.h"
#include "cell.h"

namespace olb {

template<typename T, template<typename U> class Lattice> class Cell;

/// Dirichlet condition on velocity and/or pressure
template<typename T, template<typename U> class Lattice>
class DirichletBoundaryMomenta : public Momenta<T,Lattice> {
};

template<typename T, template<typename U> class Lattice>
class EquilibriumBM : public DirichletBoundaryMomenta<T,Lattice> {
public:
    EquilibriumBM();
    EquilibriumBM(T rho_, const T u_[Lattice<T>::d]);
    virtual T computeRho(Cell<T,Lattice> const& cell) const;
    virtual void computeU (
        Cell<T,Lattice> const& cell,
        T u[Lattice<T>::d] ) const;
    virtual void computeJ (
        Cell<T,Lattice> const& cell,
        T j[Lattice<T>::d] ) const;
    virtual void computeStress (
        Cell<T,Lattice> const& cell, 
        T rho, const T u[Lattice<T>::d],
        T pi[util::TensorVal<Lattice<T> >::n] ) const;
    virtual void defineRho(Cell<T,Lattice>& cell, T rho) ;
    virtual void defineU(Cell<T,Lattice>& cell,
                         const T u[Lattice<T>::d]) ;
    virtual void defineAllMomenta (
        Cell<T,Lattice>& cell,
        T rho, const T u[Lattice<T>::d],
        const T pi[util::TensorVal<Lattice<T> >::n] );
 private:
    T rho, u[Lattice<T>::d];
};

/// Computation of velocity momenta on a velocity boundary
template<typename T, template<typename U> class Lattice,
         int direction, int orientation>
class VelocityBM : virtual public DirichletBoundaryMomenta<T,Lattice> {
public:
    /// Default Constructor: initialization to zero
    VelocityBM();
    /// Constructor with boundary initialization
    VelocityBM(const T u_[Lattice<T>::d]);

    virtual T computeRho(Cell<T,Lattice> const& cell) const;
    virtual void computeU (
        Cell<T,Lattice> const& cell,
        T u[Lattice<T>::d] ) const;
    virtual void computeJ (
        Cell<T,Lattice> const& cell,
        T j[Lattice<T>::d] ) const;
    void computeU(T u[Lattice<T>::d]) const;
    virtual void defineRho(Cell<T,Lattice>& cell, T rho) ;
    virtual void defineU(Cell<T,Lattice>& cell,
                         const T u[Lattice<T>::d]) ;
    void defineU(const T u[Lattice<T>::d]);
    virtual void defineAllMomenta (
        Cell<T,Lattice>& cell,
        T rho, const T u[Lattice<T>::d],
        const T pi[util::TensorVal<Lattice<T> >::n] );
private:
    T u[Lattice<T>::d];   ///< value of the velocity on the boundary
};

/// Computation of velocity momenta on a velocity boundary
template<typename T, template<typename U> class Lattice,
         int direction, int orientation>
class PressureBM : virtual public DirichletBoundaryMomenta<T,Lattice> {
public:
    /// Default Constructor: initialization to u=0, rho=1
    PressureBM();
    /// Constructor with boundary initialization
    PressureBM(const T values_[Lattice<T>::d]);

    virtual T computeRho(Cell<T,Lattice> const& cell) const;
    T computeRho() const;
    virtual void computeU (
        Cell<T,Lattice> const& cell,
        T u[Lattice<T>::d] ) const;
    virtual void computeJ (
        Cell<T,Lattice> const& cell,
        T j[Lattice<T>::d] ) const;
    virtual void defineRho(Cell<T,Lattice>& cell, T rho);
    void defineRho(T rho);
    virtual void defineU(Cell<T,Lattice>& cell,
                         const T u[Lattice<T>::d]);
    virtual void defineAllMomenta (
        Cell<T,Lattice>& cell,
        T rho, const T u[Lattice<T>::d],
        const T pi[util::TensorVal<Lattice<T> >::n] );

private:
    /// Velocity/Density on boundary.
    /** Contains velocity on the boundary, except for values[direction] that
     * contains a prescription for the density.
     */
    T values[Lattice<T>::d];
};

/// Here, the stress is computed from the particle distribution functions
template<typename T, template<typename U> class Lattice>
class FreeStressBM : virtual public DirichletBoundaryMomenta<T,Lattice>
{
public:
    virtual void computeStress (
            Cell<T,Lattice> const& cell,
            T rho, const T u[Lattice<T>::d],
            T pi[util::TensorVal<Lattice<T> >::n] ) const;
};

/// Use special trick to compute u resp. rho, but compute pi from part. distr. functions
template<typename T, template<typename U> class Lattice,
         template <
             typename T_, template<typename U_> class Lattice_,
             int direction_, int orientation_ >
         class HydroBM,
         int direction, int orientation>
class BasicDirichletBM
    : public FreeStressBM<T, Lattice>,
      public HydroBM<T,Lattice,direction,orientation>
{ };

/// Computation of the stress tensor for regularized boundary
template<typename T, template<typename U> class Lattice,
         int direction, int orientation>
class RegularizedBM : virtual public DirichletBoundaryMomenta<T,Lattice> {
public:
    /// Stress tensor
    virtual void computeStress (
            Cell<T,Lattice> const& cell,
            T rho, const T u[Lattice<T>::d],
            T pi[util::TensorVal<Lattice<T> >::n] ) const;
};

/// Regularized velocity boundary node
template<typename T, template<typename U> class Lattice,
         int direction, int orientation>
class RegularizedVelocityBM
    : public RegularizedBM<T,Lattice,direction,orientation>,
      public VelocityBM<T,Lattice,direction,orientation>
{
public:
    RegularizedVelocityBM() { }
    RegularizedVelocityBM(const T u_[Lattice<T>::d])
        : VelocityBM<T,Lattice,direction,orientation>(u_)
    { }
};

/// Regularized pressure boundary node
template<typename T, template<typename U> class Lattice,
         int direction, int orientation>
class RegularizedPressureBM
    : public RegularizedBM<T,Lattice,direction,orientation>,
      public PressureBM<T,Lattice,direction,orientation>
{
public:
    RegularizedPressureBM() { }
    RegularizedPressureBM(const T values_[Lattice<T>::d])
        : PressureBM<T,Lattice,direction,orientation>(values_)
    { }
};

/// In this class, the velocity is fixed
/**
 * As opposed to VelocityBM, the pressure is however not
 * computed from a special trick on the boundary, but the
 * same way it would be in the bulk.
 */
template<typename T, template<typename U> class Lattice>
class FixedVelocityBM : public Momenta<T,Lattice> {
public:
    virtual T computeRho(Cell<T,Lattice> const& cell) const;
    virtual void computeU (
        Cell<T,Lattice> const& cell,
        T u[Lattice<T>::d] ) const;
    virtual void computeJ (
        Cell<T,Lattice> const& cell,
        T j[Lattice<T>::d] ) const;
    virtual void computeStress (
        Cell<T,Lattice> const& cell, 
        T rho, const T u[Lattice<T>::d],
        T pi[util::TensorVal<Lattice<T> >::n] ) const;
    virtual void computeRhoU (
        Cell<T,Lattice> const& cell,
        T& rho, T u[Lattice<T>::d]) const;
    virtual void computeAllMomenta (
        Cell<T,Lattice> const& cell,
        T& rho, T u[Lattice<T>::d],
        T pi[util::TensorVal<Lattice<T> >::n] ) const;
    virtual void defineRho(Cell<T,Lattice>& cell, T rho);
    virtual void defineU(Cell<T,Lattice>& cell,
                         const T u[Lattice<T>::d]);
    virtual void defineRhoU (
        Cell<T,Lattice>& cell,
        T rho, const T u[Lattice<T>::d]);
    virtual void defineAllMomenta (
        Cell<T,Lattice>& cell,
        T rho, const T u[Lattice<T>::d],
        const T pi[util::TensorVal<Lattice<T> >::n] );

private:
    BulkMomenta<T,Lattice> basicMomenta;
    T fixU[Lattice<T>::d];
};

}  // namespace olb


#endif