NasaPoly2.h

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/**
 *  @file NasaPoly2.h
 *  Header for a single-species standard state object derived
 *  from @link Cantera::SpeciesThermoInterpType SpeciesThermoInterpType@endlink  based
 *  on the NASA temperature polynomial form applied to two temperature regions
 *  (see @ref spthermo and class @link Cantera::NasaPoly2 NasaPoly2@endlink).
 *
 *  Two zoned NASA polynomial parameterization
 */
 
// This file is part of Cantera. See License.txt in the top-level directory or
// at https://cantera.org/license.txt for license and copyright information.
 
#ifndef CT_NASAPOLY2_H
#define CT_NASAPOLY2_H
 
#include "cantera/thermo/SpeciesThermoInterpType.h"
#include "cantera/thermo/NasaPoly1.h"
 
namespace Cantera
{
/**
 * The NASA polynomial parameterization for two temperature ranges. This
 * parameterization expresses the heat capacity as a fourth-order polynomial.
 * Note that this is the form used in the 1971 NASA equilibrium program and by
 * the Chemkin software package, but differs from the form used in the more
 * recent NASA equilibrium program.
 *
 * Seven coefficients @f$ (a_0,\dots,a_6) @f$ are used to represent
 * @f$ c_p^0(T) @f$, @f$ h^0(T) @f$, and @f$ s^0(T) @f$ as
 * polynomials in @f$ T @f$ :
 * @f[
 * \frac{c_p(T)}{R} = a_0 + a_1 T + a_2 T^2 + a_3 T^3 + a_4 T^4
 * @f]
 * @f[
 * \frac{h^0(T)}{RT} = a_0 + \frac{a_1}{2} T + \frac{a_2}{3} T^2
 *                   + \frac{a_3}{4} T^3 + \frac{a_4}{5} T^4  + \frac{a_5}{T}.
 * @f]
 * @f[
 * \frac{s^0(T)}{R} = a_0\ln T + a_1 T + \frac{a_2}{2} T^2
 *                  + \frac{a_3}{3} T^3 + \frac{a_4}{4} T^4  + a_6.
 * @f]
 *
 * This class is designed specifically for use by the class MultiSpeciesThermo.
 *
 * @ingroup spthermo
 */
class NasaPoly2 : public SpeciesThermoInterpType
{
public:
    NasaPoly2() = default;
 
    //! Constructor with all input data
    /*!
     * @param tlow      output - Minimum temperature
     * @param thigh     output - Maximum temperature
     * @param pref      output - reference pressure (Pa).
     * @param coeffs    Vector of coefficients used to set the parameters for
     *                  the standard state [Tmid, 7 high-T coeffs, 7 low-T
     *                  coeffs]. This is the coefficient order used in the
     *                  standard NASA format.
     */
    NasaPoly2(double tlow, double thigh, double pref, span<const double> coeffs) :
        SpeciesThermoInterpType(tlow, thigh, pref),
        m_midT(coeffs[0]),
        mnp_low(tlow, coeffs[0], pref, coeffs.subspan(8, 7)),
        mnp_high(coeffs[0], thigh, pref, coeffs.subspan(1, 7)) {
    }
 
    void setMinTemp(double Tmin) override {
        SpeciesThermoInterpType::setMinTemp(Tmin);
        mnp_low.setMinTemp(Tmin);
    }
 
    void setMaxTemp(double Tmax) override {
        SpeciesThermoInterpType::setMaxTemp(Tmax);
        mnp_high.setMaxTemp(Tmax);
    }
 
    void setRefPressure(double Pref) override {
        SpeciesThermoInterpType::setRefPressure(Pref);
        mnp_low.setRefPressure(Pref);
        mnp_high.setRefPressure(Pref);
    }
 
    /**
     * @param Tmid  Temperature [K] at the boundary between the low and high
     *              temperature polynomials
     * @param low   Vector of 7 coefficients for the low temperature polynomial
     * @param high  Vector of 7 coefficients for the high temperature polynomial
     */
    void setParameters(double Tmid, span<const double> low, span<const double> high);
 
    int reportType() const override {
        return NASA2;
    }
 
    size_t temperaturePolySize() const override { return 6; }
 
    void updateTemperaturePoly(double T, span<double> T_poly) const override {
        mnp_low.updateTemperaturePoly(T, T_poly);
    }
 
    //! @copydoc NasaPoly1::updateProperties
    void updateProperties(span<const double> tt, double& cp_R, double& h_RT,
                          double& s_R) const override {
        if (tt[0] <= m_midT) {
            mnp_low.updateProperties(tt, cp_R, h_RT, s_R);
        } else {
            mnp_high.updateProperties(tt, cp_R, h_RT, s_R);
        }
    }
 
    void updatePropertiesTemp(const double temp, double& cp_R, double& h_RT,
                              double& s_R) const override {
        if (temp <= m_midT) {
            mnp_low.updatePropertiesTemp(temp, cp_R, h_RT, s_R);
        } else {
            mnp_high.updatePropertiesTemp(temp, cp_R, h_RT, s_R);
        }
    }
 
    size_t nCoeffs() const override { return 15; }
 
    void reportParameters(size_t& n, int& type, double& tlow, double& thigh,
                          double& pref, span<double> coeffs) const override {
        mnp_high.reportParameters(n, type, coeffs[0], thigh, pref, coeffs.subspan(1));
        mnp_low.reportParameters(n, type, tlow, coeffs[0], pref, coeffs.subspan(8));
        type = NASA2;
    }
 
    void getParameters(AnyMap& thermo) const override;
 
    double reportHf298() const override {
        if (298.15 <= m_midT) {
            return mnp_low.reportHf298();
        } else {
            return mnp_high.reportHf298();
        }
    }
 
    void resetHf298() override {
        mnp_low.resetHf298();
        mnp_high.resetHf298();
    }
 
    void modifyOneHf298(const size_t k, const double Hf298New) override {
        double h298now = reportHf298();
        double delH = Hf298New - h298now;
        double h = mnp_low.reportHf298();
        double hnew = h + delH;
        mnp_low.modifyOneHf298(k, hnew);
        h = mnp_high.reportHf298();
        hnew = h + delH;
        mnp_high.modifyOneHf298(k, hnew);
    }
 
    void validate(const string& name) override;
 
protected:
    //! Midrange temperature
    double m_midT = 0.0;
    //! NasaPoly1 object for the low temperature region.
    NasaPoly1 mnp_low;
    //! NasaPoly1 object for the high temperature region.
    NasaPoly1 mnp_high;
};
 
}
#endif