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
 */

/* $Author: hkmoffa $
 * $Revision: 279 $
 * $Date: 2009-12-05 14:08:43 -0500 (Sat, 05 Dec 2009) $
 */

// Copyright 2001  California Institute of Technology


#ifndef CT_NASAPOLY2_H
#define CT_NASAPOLY2_H

#include "SpeciesThermoInterpType.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 
   * GeneralSpeciesThermo.
   *
   * @ingroup spthermo
   */
  class NasaPoly2 : public SpeciesThermoInterpType {

  public:

    //! Empty constructor
    NasaPoly2() 
      : m_lowT(0.0),
        m_midT(0.0), 
        m_highT (0.0),
        m_Pref(0.0),
        mnp_low(0),
        mnp_high(0), 
        m_index(0),
        m_coeff(array_fp(15)) {
    }

    //! Full Constructor
    /*!
     * @param n         Species index
     * @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.
     */
    NasaPoly2(int n, doublereal tlow, doublereal thigh, doublereal pref,
              const doublereal* coeffs) :
      m_lowT(tlow),
      m_highT(thigh),
      m_Pref(pref),
      mnp_low(0),
      mnp_high(0),
      m_index(n),
      m_coeff(array_fp(15)) {

      std::copy(coeffs, coeffs + 15, m_coeff.begin());
      m_midT = coeffs[0];
      mnp_low  = new NasaPoly1(m_index, m_lowT, m_midT,
                               m_Pref, &m_coeff[1]);
      mnp_high = new NasaPoly1(m_index, m_midT, m_highT,
                               m_Pref, &m_coeff[8]);
    }

    //! Copy Constructor
    /*!
     * @param b objecto to be copied.
     */
    NasaPoly2(const NasaPoly2& b) :
      m_lowT(b.m_lowT),
      m_midT(b.m_midT),
      m_highT(b.m_highT),
      m_Pref(b.m_Pref),
      mnp_low(0),
      mnp_high(0),
      m_index(b.m_index),
      m_coeff(array_fp(15)) {

      std::copy(b.m_coeff.begin(),
                b.m_coeff.begin() + 15,
                m_coeff.begin());
      mnp_low  = new NasaPoly1(m_index, m_lowT, m_midT,
                               m_Pref, &m_coeff[1]);
      mnp_high = new NasaPoly1(m_index, m_midT, m_highT,
                               m_Pref, &m_coeff[8]);
    }

    //! Assignment operator
    /*!
     * @param b objecto to be copied.
     */
    NasaPoly2& operator=(const NasaPoly2& b) {
      if (&b != this) {
        m_lowT   = b.m_lowT;
        m_midT   = b.m_midT;
        m_highT  = b.m_highT;
        m_Pref   = b.m_Pref;
        m_index  = b.m_index;
        std::copy(b.m_coeff.begin(),
                  b.m_coeff.begin() + 15,
                  m_coeff.begin());
        if (mnp_low) delete mnp_low;
        if (mnp_high) delete mnp_high;
        mnp_low  = new NasaPoly1(m_index, m_lowT, m_midT, 
                                 m_Pref, &m_coeff[1]);
        mnp_high = new NasaPoly1(m_index, m_midT, m_highT, 
                                 m_Pref, &m_coeff[8]);
      }
      return *this;
    }

    //! destructor
    virtual ~NasaPoly2(){
      delete mnp_low;
      delete mnp_high;
    }

    //! duplicator
    virtual SpeciesThermoInterpType *
    duplMyselfAsSpeciesThermoInterpType() const {
      NasaPoly2* np = new NasaPoly2(*this);
      return (SpeciesThermoInterpType *) np;
    }

    //! Returns the minimum temperature that the thermo
    //! parameterization is valid
    doublereal minTemp() const     { return m_lowT;}

    //! Returns the maximum temperature that the thermo
    //! parameterization is valid
    doublereal maxTemp() const     { return m_highT;}

    //! Returns the reference pressure (Pa)
    doublereal refPressure() const { return m_Pref; }

    //! Returns an integer representing the type of parameterization
    virtual int reportType() const { return NASA2; }

    //! Returns an integer representing the species index
    virtual int speciesIndex() const { return m_index; }
  

    //! Update the properties for this species, given a temperature polynomial
    /*!
     * This method is called with a pointer to an array containing the functions of
     * temperature needed by this  parameterization, and three pointers to arrays where the
     * computed property values should be written. This method updates only one value in
     * each array.
     *
     * Temperature Polynomial:
     *  tt[0] = t;
     *  tt[1] = t*t;
     *  tt[2] = m_t[1]*t;
     *  tt[3] = m_t[2]*t;
     *  tt[4] = 1.0/t;
     *  tt[5] = std::log(t);
     *
     * @param tt  vector of temperature polynomials
     * @param cp_R    Vector of Dimensionless heat capacities.
     *                (length m_kk).
     * @param h_RT    Vector of Dimensionless enthalpies.
     *                (length m_kk).
     * @param s_R     Vector of Dimensionless entropies.
     *                (length m_kk).
     */
    void updateProperties(const doublereal* tt, 
                          doublereal* cp_R, doublereal* h_RT, doublereal* s_R) const {
          
      double T = tt[0];
      if (T <= m_midT) {
        mnp_low->updateProperties(tt, cp_R, h_RT, s_R);
      } else {
        mnp_high->updateProperties(tt, cp_R, h_RT, s_R);
      }
    }

    //! Compute the reference-state property of one species
    /*!
     * Given temperature T in K, this method updates the values of
     * the non-dimensional heat capacity at constant pressure,
     * enthalpy, and entropy, at the reference pressure, Pref
     * of one of the species. The species index is used
     * to reference into the cp_R, h_RT, and s_R arrays.
     *
     * @param temp    Temperature (Kelvin)
     * @param cp_R    Vector of Dimensionless heat capacities.
     *                (length m_kk).
     * @param h_RT    Vector of Dimensionless enthalpies.
     *                (length m_kk).
     * @param s_R     Vector of Dimensionless entropies.
     *                (length m_kk).
     */
    void updatePropertiesTemp(const doublereal temp, 
                              doublereal* cp_R,
                              doublereal* h_RT, 
                              doublereal* s_R) const {
      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);
      }
    }

    //!This utility function reports back the type of 
    //! parameterization and all of the parameters for the 
    //! species, index.
    /*!
     * All parameters are output variables
     *
     * @param n         Species index
     * @param type      Integer type of the standard type
     * @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.
     */
    void reportParameters(int &n, int &type,
                          doublereal &tlow, doublereal &thigh,
                          doublereal &pref,
                          doublereal* const coeffs) const {
      n = m_index;
      type = NASA2;
      tlow = m_lowT;
      thigh = m_highT;
      pref = m_Pref;
      for (int i = 0; i < 15; i++) {
        coeffs[i] = m_coeff[i];
      }
    }

#ifdef H298MODIFY_CAPABILITY

    doublereal reportHf298(doublereal* const h298 = 0) const {
      double h;
      if (298.15 <= m_midT) {
        h = mnp_low->reportHf298(0);
      } else {
        h = mnp_high->reportHf298(0);
      }
      if (h298) {
        h298[m_index] = h;
      }
      return h;
    }

    void modifyOneHf298(const int k, const doublereal Hf298New) {
      if (k != m_index) return;
 
      doublereal h298now = reportHf298(0);
      doublereal delH = Hf298New - h298now;
      double h = mnp_low->reportHf298(0);
      double hnew = h + delH;
      mnp_low->modifyOneHf298(k, hnew);
      h  = mnp_high->reportHf298(0);
      hnew = h + delH;
      mnp_high->modifyOneHf298(k, hnew);
    }

#endif

  protected:
    //!  lowest valid temperature
    doublereal m_lowT;   
    //! Midrange temperature
    doublereal m_midT;
    //! Highest valid temperatre
    doublereal m_highT;  
    //! Reference state pressure
    doublereal m_Pref;
    //! pointer to the NasaPoly1 object for the low temperature region.
    NasaPoly1 *mnp_low;
    //! pointer to the NasaPoly1 object for the high temperature region.
    NasaPoly1 *mnp_high;
    //! species index
    int m_index;           
    //! array of polynomial coefficients
    array_fp m_coeff;    

  };

}
#endif