n2.hh

Go to the documentation of this file.

// -*- mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
// vi: set et ts=4 sw=4 sts=4:
/*****************************************************************************
 *   See the file COPYING for full copying permissions.                      *
 *                                                                           *
 *   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 3 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, see <http://www.gnu.org/licenses/>.   *
 *****************************************************************************/
#ifndef DUMUX_N2_HH
#define DUMUX_N2_HH
 
#include <dumux/material/idealgas.hh>
 
#include <cmath>
 
#include <dumux/material/components/base.hh>
#include <dumux/material/components/gas.hh>
 
namespace Dumux {
namespace Components {
 
template <class Scalar>
class N2
: public Components::Base<Scalar, N2<Scalar> >
, public Components::Gas<Scalar, N2<Scalar> >
{
    using IdealGas = Dumux::IdealGas<Scalar>;
 
public:
    static std::string name()
    { return "N2"; }
 
    static constexpr Scalar molarMass()
    { return 28.0134e-3;}
 
    static Scalar criticalTemperature()
    { return 126.192; /* [K] */ }
 
    static Scalar criticalPressure()
    { return 3.39858e6; /* [N/m^2] */ }
 
    static Scalar tripleTemperature()
    { return 63.151; /* [K] */ }
 
    static Scalar triplePressure()
    { return 12.523e3; /* [N/m^2] */ }
 
    static Scalar vaporPressure(Scalar T)
    {
        if (T > criticalTemperature())
            return criticalPressure();
        if (T < tripleTemperature())
            return 0; // N2 is solid: We don't take sublimation into
                      // account
 
        // note: this is the ancillary equation given on page 1368
        using std::sqrt;
        Scalar sigma = Scalar(1.0) - T/criticalTemperature();
        Scalar sqrtSigma = sqrt(sigma);
        const Scalar N1 = -6.12445284;
        const Scalar N2 = 1.26327220;
        const Scalar N3 = -0.765910082;
        const Scalar N4 = -1.77570564;
 
        using std::exp;
        return
            criticalPressure() *
            exp(criticalTemperature()/T*
                     (sigma*(N1 +
                             sqrtSigma*N2 +
                             sigma*(sqrtSigma*N3 +
                                    sigma*sigma*sigma*N4))));
    }
 
    static Scalar gasDensity(Scalar temperature, Scalar pressure)
    {
        // Assume an ideal gas
        return IdealGas::density(molarMass(), temperature, pressure);
    }
 
    static Scalar gasMolarDensity(Scalar temperature, Scalar pressure)
    { return IdealGas::molarDensity(temperature, pressure); }
 
    static constexpr bool gasIsCompressible()
    { return true; }
 
    static constexpr bool gasIsIdeal()
    { return true; }
 
    static Scalar gasPressure(Scalar temperature, Scalar density)
    {
        // Assume an ideal gas
        return IdealGas::pressure(temperature, density/molarMass());
    }
 
    static const Scalar gasEnthalpy(Scalar temperature,
                                    Scalar pressure)
    {
        return gasHeatCapacity(temperature, pressure) * temperature;
    }
 
    static const Scalar gasInternalEnergy(Scalar temperature,
                                          Scalar pressure)
    {
        return
            gasEnthalpy(temperature, pressure) -
            1/molarMass()* // conversion from [J/(mol K)] to [J/(kg K)]
            IdealGas::R*temperature; // = pressure * spec. volume for an ideal gas
    }
 
    static const Scalar gasHeatCapacity(Scalar T,
                                        Scalar pressure)
    {
        // method of Joback
        const Scalar cpVapA = 31.15;
        const Scalar cpVapB = -0.01357;
        const Scalar cpVapC = 2.680e-5;
        const Scalar cpVapD = -1.168e-8;
 
        return
            1/molarMass()* // conversion from [J/(mol K)] to [J/(kg K)]
            (cpVapA + T*
              (cpVapB/2 + T*
                (cpVapC/3 + T*
                  (cpVapD/4))));
    }
 
    static Scalar gasViscosity(Scalar temperature, Scalar pressure)
    {
        const Scalar Tc = criticalTemperature();
        const Scalar Vc = 90.1; // critical specific volume [cm^3/mol]
        const Scalar omega = 0.037; // accentric factor
        const Scalar M = molarMass() * 1e3; // molar mas [g/mol]
        const Scalar dipole = 0.0; // dipole moment [debye]
 
        using std::sqrt;
        Scalar mu_r4 = 131.3 * dipole / sqrt(Vc * Tc);
        mu_r4 *= mu_r4;
        mu_r4 *= mu_r4;
 
        using std::pow;
        using std::exp;
        Scalar Fc = 1 - 0.2756*omega + 0.059035*mu_r4;
        Scalar Tstar = 1.2593 * temperature/Tc;
        Scalar Omega_v =
            1.16145*pow(Tstar, -0.14874) +
            0.52487*exp(- 0.77320*Tstar) +
            2.16178*exp(- 2.43787*Tstar);
        Scalar mu = 40.785*Fc*sqrt(M*temperature)/(pow(Vc, 2./3)*Omega_v);
 
        // conversion from micro poise to Pa s
        return mu/1e6 / 10;
    }
 
    static Scalar gasThermalConductivity(Scalar temperature, Scalar pressure)
    {
        return 6.525e-5 * (temperature - 273.15) + 0.024031;
    }
};
 
} // end namespace Components
 
} // end namespace Dumux
 
#endif