NasaPoly1.h

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/**
 *  @file NasaPoly1.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 one temperature region
 *  (see \ref spthermo and class \link Cantera::NasaPoly1 NasaPoly1\endlink).
 *
 *  This parameterization has one NASA temperature region.
 */


#ifndef CT_NASAPOLY1_H
#define CT_NASAPOLY1_H


/* $Author: hkmoffa $
 * $Revision: 306 $
 * $Date: 2009-12-09 12:29:23 -0500 (Wed, 09 Dec 2009) $
 */

// Copyright 2001  California Institute of Technology


#include "global.h"
#include "SpeciesThermoInterpType.h"

namespace Cantera {

  /**
   * The NASA polynomial parameterization for one temperature range.
   * 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 class NasaThermo.
   * @ingroup spthermo
   */
  class NasaPoly1 : public SpeciesThermoInterpType {

  public:

    //! Empty constructor
    NasaPoly1() 
      : m_lowT(0.0), m_highT (0.0),
        m_Pref(0.0), m_index (0), m_coeff(array_fp(7)) {}


    //! constructor used in templated instantiations
    /*!
     * @param n            Species index
     * @param tlow         Minimum temperature
     * @param thigh        Maximum temperature
     * @param pref         reference pressure (Pa).
     * @param coeffs       Vector of coefficients used to set the
     *                     parameters for the standard state.
     */
    NasaPoly1(int n, doublereal tlow, doublereal thigh, doublereal pref,
              const doublereal* coeffs) :
      m_lowT      (tlow),
      m_highT     (thigh),
      m_Pref      (pref),
      m_index     (n),
      m_coeff     (array_fp(7)) {
      std::copy(coeffs, coeffs + 7, m_coeff.begin());
    }

    //! copy constructor
    /*!
     * @param b object to be copied
     */
    NasaPoly1(const NasaPoly1& b) :
      m_lowT      (b.m_lowT),
      m_highT     (b.m_highT),
      m_Pref      (b.m_Pref),
      m_index     (b.m_index),
      m_coeff     (array_fp(7)) {
      std::copy(b.m_coeff.begin(),
                b.m_coeff.begin() + 7,
                m_coeff.begin());
    }

    //! assignment operator
    /*!
     * @param b object to be copied
     */
    NasaPoly1& operator=(const NasaPoly1& b) {
      if (&b != this) {
        m_lowT   = b.m_lowT;
        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() + 7,
                  m_coeff.begin());
      }
      return *this;
    }

    //! Destructor
    virtual ~NasaPoly1(){}

    //! duplicator
    virtual SpeciesThermoInterpType *
    duplMyselfAsSpeciesThermoInterpType() const {
      NasaPoly1* np = new NasaPoly1(*this);
      return (SpeciesThermoInterpType *) np;
    }

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

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

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

    //! Returns an integer representing the type of parameterization
    virtual int reportType() const { return NASA1; }
      
     //! 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).
     */
    virtual void updateProperties(const doublereal* tt, 
                                  doublereal* cp_R, doublereal* h_RT, doublereal* s_R) const {
          
      doublereal ct0 = m_coeff[2];          // a0 
      doublereal ct1 = m_coeff[3]*tt[0];    // a1 * T
      doublereal ct2 = m_coeff[4]*tt[1];    // a2 * T^2
      doublereal ct3 = m_coeff[5]*tt[2];    // a3 * T^3
      doublereal ct4 = m_coeff[6]*tt[3];    // a4 * T^4
 
      doublereal cp, h, s;
      cp = ct0 + ct1 + ct2 + ct3 + ct4;
      h = ct0 + 0.5*ct1 + OneThird*ct2 + 0.25*ct3 + 0.2*ct4
        + m_coeff[0]*tt[4];               // last term is a5/T
      s = ct0*tt[5] + ct1 + 0.5*ct2 + OneThird*ct3
        +0.25*ct4 + m_coeff[1];           // last term is a6

      // return the computed properties in the location in the output 
      // arrays for this species
      cp_R[m_index] = cp;
      h_RT[m_index] = h;
      s_R[m_index] = s;
      //writelog("NASA1: for species "+int2str(m_index)+", h_RT = "+
      //    fp2str(h)+"\n");
    }

 
    //! 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).
     */
    virtual void updatePropertiesTemp(const doublereal temp, 
                                      doublereal* cp_R, doublereal* h_RT, 
                                      doublereal* s_R) const {
      double tPoly[6];
      tPoly[0]  = temp;
      tPoly[1]  = temp * temp;
      tPoly[2]  = tPoly[1] * temp;
      tPoly[3]  = tPoly[2] * temp;
      tPoly[4]  = 1.0 / temp;
      tPoly[5]  = std::log(temp);
      updateProperties(tPoly, 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.
     */
    virtual void reportParameters(int &n, int &type,
                                  doublereal &tlow, doublereal &thigh,
                                  doublereal &pref,
                                  doublereal* const coeffs) const {
      n = m_index;
      type = NASA1;
      tlow = m_lowT;
      thigh = m_highT;
      pref = m_Pref;
      coeffs[5] = m_coeff[0];
      coeffs[6] = m_coeff[1];
      for (int i = 2; i < 7; i++) {
        coeffs[i-2] = m_coeff[i];
      }
#ifdef WARN_ABOUT_CHANGES_FROM_VERSION_1_6
      cout << "************************************************\n"
        cout << "Warning: NasaPoly1::reportParameters now returns \n"
           << "the coefficient array in the same order as in\n"
           << "the input file.  See file NasaPoly1.h" << endl;
      cout << "************************************************\n"
#endif
        }

    //! Modify parameters for the standard state
    /*!
     * @param coeffs   Vector of coefficients used to set the
     *                 parameters for the standard state.
     */
    virtual void modifyParameters(doublereal* coeffs) {
      m_coeff[0] = coeffs[5];
      m_coeff[1] = coeffs[6];
      for (int i = 0; i < 5; i++) {
        m_coeff[i+2] = coeffs[i];
      }            
    }

#ifdef H298MODIFY_CAPABILITY

    virtual doublereal reportHf298(doublereal* const h298 = 0) const {
      double tt[6];
      double temp = 298.15;
      tt[0]  = temp;
      tt[1]  = temp * temp;
      tt[2]  = tt[1] * temp;
      tt[3]  = tt[2] * temp;
      tt[4]  = 1.0 / temp;
      //tt[5]  = std::log(temp);
      doublereal ct0 = m_coeff[2];          // a0 
      doublereal ct1 = m_coeff[3]*tt[0];    // a1 * T
      doublereal ct2 = m_coeff[4]*tt[1];    // a2 * T^2
      doublereal ct3 = m_coeff[5]*tt[2];    // a3 * T^3
      doublereal ct4 = m_coeff[6]*tt[3];    // a4 * T^4
 
      double h_RT = ct0 + 0.5*ct1 + OneThird*ct2 + 0.25*ct3 + 0.2*ct4
        + m_coeff[0]*tt[4];               // last t
      
      double h = h_RT * GasConstant * temp;
      if (h298) {
        h298[m_index] = h; 
      }
      return h;
    }

    virtual void modifyOneHf298(const int k, const doublereal Hf298New) {
      if (k != m_index) return;
      double hcurr = reportHf298(0);
      double delH = Hf298New - hcurr;
      m_coeff[0] += (delH) / GasConstant;
    }
    
#endif

  protected:
    //! lowest valid temperature
    doublereal m_lowT;    
    //! highest valid temperature
    doublereal m_highT;   
    //! standard-state pressure
    doublereal m_Pref;     
    //! species index
    int m_index;  
    //! array of polynomial coefficients       
    array_fp m_coeff;    

  };

}
#endif