Gas.H

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#ifndef MODEL_GAS_H_
#define MODEL_GAS_H_
 
#include <vector>
#include <cmath>
#include <memory>
#include "Model/Gas/Thermo/CpConstant.H"
#include "Model/Gas/Transport/Mixture_Averaged.H"
#include "Model/Gas/EOS/CPG.H"
#include "Util/Util.H"
#include "Set/Base.H"
#include "Set/Set.H"
#include "IO/ParmParse.H"
 
namespace Model {
namespace Gas {
 
class Gas {
protected:
public:
    int nspecies;
    std::vector<double> MW;      // Species molecular weights, kg/kmol
    Thermo::Thermo *thermo = nullptr;
    Transport::Transport *transport = nullptr;
    EOS::EOS *eos = nullptr;
 
public:
    virtual ~Gas() {
        delete thermo;
        delete transport;
        delete eos;
    }
 
    static void Parse(Gas & value, IO::ParmParse & pp)
    {
        // number of species
        pp.queryarr_required("mw",value.MW,Unit::Mass()/Unit::Amount());
        value.nspecies = value.MW.size();
 
        delete value.thermo;
        value.thermo = nullptr;
        // thermo model
        pp.select<Thermo::CpConstant>("thermo", value.thermo, value.nspecies);
 
        delete value.transport;
        value.transport = nullptr;
        // transport model
        pp.select<Transport::Mixture_Averaged>("transport", value.transport, value.nspecies, value.MW, value.thermo);
 
        delete value.eos;
        value.eos = nullptr;
        // eos model
        pp.select<EOS::CPG>("eos", value.eos, &value);
    }
    
public:
    // Thermodynamic quantities
    double cp_mol(double T, Set::Patch<const Set::Scalar>& X, int i, int j, int k) const;
    double enthalpy_mol(double T, Set::Patch<const Set::Scalar>& X, int i, int j, int k) const;
    double entropy_mol(double T, Set::Patch<const Set::Scalar>& X, int i, int j, int k) const;
 
    // Transport quantities
    double dynamic_viscosity(double T, Set::Patch<const Set::Scalar>& X, int i, int j, int k) const;
    double thermal_conductivity(double T, Set::Patch<const Set::Scalar>& X, int i, int j, int k) const;
    void diffusion_coeffs(Set::Patch<Set::Scalar>& DKM, double T, double P, Set::Patch<const Set::Scalar>& X, int i, int j, int k);
 
    // EOS
    double ComputeT(
            double density, double momentumx, double momentumy, double E, double Tguess,
            Set::Patch<const Set::Scalar>& X, int i, int j, int k, double rtol=1e-12) const;
    double ComputeT(
            double pressure, double density,
            Set::Patch<const Set::Scalar>& X, int i, int j, int k) const;
    double ComputeP(double density, double T, Set::Patch<const Set::Scalar>& X, int i, int j, int k) const;
    double ComputeE(    
            double density, double momentumx, double momentumy, double T,
            Set::Patch<const Set::Scalar>& X, int i, int j, int k) const;
 
// Universal methods inherent to Gas
public:
    void ComputeLocalFractions(
            Set::Patch<const Set::Scalar>& density_mf,
            Set::Patch<Set::Scalar>& mass_fraction_mf,
            Set::Patch<Set::Scalar>& mole_fraction_mf,
            const int i, const int j, const int k)
    {
        // In place update for mass and mole fractions
        // This needs to be called before any other functions if cell composition 
        // has changed, since they are dependent on mole fraction
        double density = 0.0;
        double moles = 0.0;
        for (int n=0; n<nspecies; ++n) {
            density += density_mf(i,j,k,n);
            moles += density_mf(i,j,k,n) / MW[n];
        }
        for (int n=0; n<nspecies; ++n) {
            mass_fraction_mf(i,j,k,n) = density_mf(i,j,k,n) / density;
            mole_fraction_mf(i,j,k,n) = density_mf(i,j,k,n) / MW[n] / moles;
        }
    }
    double GetMW(Set::Patch<const Set::Scalar>& X, int i, int j, int k) const {
        // Molecular weight, kg/kmol
        double mw = 0.0;
        for (int n=0; n<nspecies; ++n) mw += X(i,j,k,n) * MW[n];
        return mw;
    }
    double ComputeD(Set::Patch<const Set::Scalar>& rhoY, int i, int j, int k) const {
        // Mixture density kg/m^3
        double rho = 0.0;
        for (int n=0; n<nspecies; ++n) rho += rhoY(i,j,k,n);
        return rho;
    }
    double R(Set::Patch<const Set::Scalar>& X, int i, int j, int k) const { 
        // Specific gas constant, J/(kg-K)
        return Set::Constant::Rg/GetMW(X, i, j, k);
    }
    double cp_mass(double T, Set::Patch<const Set::Scalar>& X, int i, int j, int k) const {
        // Specific heat (constant pressure), J/(kg-K)
        return cp_mol(T, X, i, j, k) / GetMW(X, i, j, k);
    }
    double cv_mol(double T, Set::Patch<const Set::Scalar>& X, int i, int j, int k) const {
        // Specific heat (constant volume), J/(kmol-K)
        return cp_mol(T, X, i, j, k) - Set::Constant::Rg;
    }
    double cv_mass(double T, Set::Patch<const Set::Scalar>& X, int i, int j, int k) const {
        // Specific heat (constant volume), J/(kg-K)
        return cv_mol(T, X, i, j, k) / GetMW(X, i, j, k);
    }
    double gamma(double T, Set::Patch<const Set::Scalar>& X, int i, int j, int k) const  {
        // Specific heat ratio
        return cp_mol(T, X, i, j, k) / cv_mol(T, X, i, j, k);
    }
    double enthalpy_mass(double T, Set::Patch<const Set::Scalar>& X, int i, int j, int k) const {
        // Specific enthalpy, J/kg
        return enthalpy_mol(T, X, i, j, k) / GetMW(X, i, j, k);
    }
    double entropy_mass(double T, Set::Patch<const Set::Scalar>& X, int i, int j, int k) const {
        // Specific entropy, J/(kg-K)
        return entropy_mol(T, X, i, j, k) / GetMW(X, i, j, k);
    }
 
}; // class Gas
 
} // namespace Gas
} // namespace Model
 
#endif