Nasa9Poly1.cpp

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/**
 *  @file Nasa9Poly1.cpp
 *  Definitions for a single-species standard state object derived
 *  from
 *  \link Cantera::SpeciesThermoInterpType SpeciesThermoInterpType\endlink
 *  based
 *  on the NASA 9 coefficient temperature polynomial form applied to one temperature region
 *  (see \ref spthermo and class \link Cantera::Nasa9Poly1 Nasa9Poly1\endlink).
 *
 *  This parameterization has one NASA temperature region.
 */
// Copyright 2007  Sandia National Laboratories

#include "cantera/thermo/Nasa9Poly1.h"

namespace Cantera
{


// The NASA 9 polynomial parameterization for one temperature range.
/*
 * This parameterization expresses the heat capacity via a
 * 7 coefficient polynomial.
 *
 *  Note that this is the form used in the
 * 2002 NASA equilibrium program
 *
 *  "NASA Glenn Coefficients for Calculating Thermodynamic
 *  Properties of Individual Species,"
 *  B. J. McBride, M. J. Zehe, S. Gordon
 *  NASA/TP-2002-211556, Sept. 2002
 *
 *
 * Nine 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^0(T)}{R} = a_0 T^{-2} + a_1 T^{-1} + a_2 + a_3 T
 *                  + a_4 T^2 + a_5 T^3 + a_6 T^4
 * \f]
 *
 * \f[
 * \frac{H^0(T)}{RT} = - a_0 T^{-2} + a_1 \frac{\ln(T)}{T} + a_2
 * + a_3 T + a_4 T^2  + a_5 T^3 + a_6 T^4 + \frac{a_7}{T}
 * \f]
 *
 * \f[
 * \frac{s^0(T)}{R} = - \frac{a_0}{2} T^{-2} - a_1 T^{-1} + a_2 \ln(T)
 +    + a_3 T  \frac{a_4}{2} T^2 + \frac{a_5}{3} T^3  + \frac{a_6}{4} T^4 + a_8
 * \f]
 *
 *  The standard state is assumed to be the ideal gas at the
 *  standard pressure of 1 bar, for gases.
 *  For condensed species, the standard state is the
 *  pure crystalline or liquid substance at the standard
 *  pressure of 1 atm.
 *
 * These NASA representations may have more than 2 temperature regions.
 *
 * @ingroup spthermo
 */


//! Empty constructor
Nasa9Poly1::Nasa9Poly1()
    : m_lowT(0.0), m_highT(0.0),
      m_Pref(1.0E5), m_index(0), m_coeff(vector_fp(9)) {}


// 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.
 */
Nasa9Poly1::Nasa9Poly1(size_t n, doublereal tlow, doublereal thigh,
                       doublereal pref,
                       const doublereal* coeffs) :
    m_lowT(tlow),
    m_highT(thigh),
    m_Pref(pref),
    m_index(n),
    m_coeff(vector_fp(9))
{
    std::copy(coeffs, coeffs + 9, m_coeff.begin());
}

// copy constructor
/*
 * @param b object to be copied
 */
Nasa9Poly1::Nasa9Poly1(const Nasa9Poly1& b) :
    m_lowT(b.m_lowT),
    m_highT(b.m_highT),
    m_Pref(b.m_Pref),
    m_index(b.m_index),
    m_coeff(vector_fp(9))
{
    std::copy(b.m_coeff.begin(),
              b.m_coeff.begin() + 9,
              m_coeff.begin());
}

// assignment operator
/*
 * @param b object to be copied
 */
Nasa9Poly1& Nasa9Poly1::operator=(const Nasa9Poly1& 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() + 9,
                  m_coeff.begin());
    }
    return *this;
}

// Destructor
Nasa9Poly1::~Nasa9Poly1()
{
}

// duplicator
SpeciesThermoInterpType*
Nasa9Poly1::duplMyselfAsSpeciesThermoInterpType() const
{
    Nasa9Poly1* np = new Nasa9Poly1(*this);
    return (SpeciesThermoInterpType*) np;
}

// Returns the minimum temperature that the thermo
// parameterization is valid
doublereal Nasa9Poly1::minTemp() const
{
    return m_lowT;
}

// Returns the maximum temperature that the thermo
// parameterization is valid
doublereal Nasa9Poly1::maxTemp() const
{
    return m_highT;
}

// Returns the reference pressure (Pa)
doublereal Nasa9Poly1::refPressure() const
{
    return m_Pref;
}

// Returns an integer representing the type of parameterization
int Nasa9Poly1::reportType() const
{
    return NASA9;
}

// Returns an integer representing the species index
size_t Nasa9Poly1::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] = t*t*t;
 *  tt[3] = t*t*t*t;
 *  tt[4] = 1.0/t;
 *  tt[5] = 1.0/(t*t);
 *  tt[6] = 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 Nasa9Poly1::updateProperties(const doublereal* tt,
                                  doublereal* cp_R, doublereal* h_RT,
                                  doublereal* s_R) const
{

    doublereal ct0 = m_coeff[0] * tt[5];   // a0 / (T^2)
    doublereal ct1 = m_coeff[1] * tt[4];   // a1 / T
    doublereal ct2 = m_coeff[2];           // a2
    doublereal ct3 = m_coeff[3] * tt[0];   // a3 * T
    doublereal ct4 = m_coeff[4] * tt[1];   // a4 * T^2
    doublereal ct5 = m_coeff[5] * tt[2];   // a5 * T^3
    doublereal ct6 = m_coeff[6] * tt[3];   // a6 * T^4


    doublereal cpdivR = ct0 + ct1 + ct2 + ct3 + ct4 + ct5 + ct6;
    doublereal hdivRT = -ct0 + tt[6]*ct1  + ct2 + 0.5*ct3 + OneThird*ct4
                        + 0.25*ct5  + 0.2*ct6 + m_coeff[7] * tt[4];
    doublereal sdivR  = -0.5*ct0  - ct1 + tt[6]*ct2  + ct3  + 0.5*ct4
                        + OneThird*ct5 + 0.25*ct6 + m_coeff[8];

    // return the computed properties in the location in the output
    // arrays for this species
    cp_R[m_index] = cpdivR;
    h_RT[m_index] = hdivRT;
    s_R[m_index] = sdivR;
    //writelog("NASA9poly1: 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.
 *
 * Temperature Polynomial:
 *  tt[0] = t;
 *  tt[1] = t*t;
 *  tt[2] = t*t*t;
 *  tt[3] = t*t*t*t;
 *  tt[4] = 1.0/t;
 *  tt[5] = 1.0/(t*t);
 *  tt[6] = std::log(t);
 *
 * @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 Nasa9Poly1::updatePropertiesTemp(const doublereal temp,
                                      doublereal* cp_R, doublereal* h_RT,
                                      doublereal* s_R) const
{
    double tPoly[7];
    tPoly[0]  = temp;
    tPoly[1]  = temp * temp;
    tPoly[2]  = tPoly[1] * temp;
    tPoly[3]  = tPoly[2] * temp;
    tPoly[4]  = 1.0 / temp;
    tPoly[5]  = tPoly[4] / temp;
    tPoly[6]  = 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.
 */
void Nasa9Poly1::reportParameters(size_t& n, int& type,
                                  doublereal& tlow, doublereal& thigh,
                                  doublereal& pref,
                                  doublereal* const coeffs) const
{
    n = m_index;
    type = NASA9;
    tlow = m_lowT;
    thigh = m_highT;
    pref = m_Pref;
    coeffs[0] = 1;
    coeffs[1] = m_lowT;
    coeffs[2] = m_highT;
    for (int i = 0; i < 9; i++) {
        coeffs[i+3] = m_coeff[i];
    }

}

// Modify parameters for the standard state
/*
 * @param coeffs   Vector of coefficients used to set the
 *                 parameters for the standard state.
 */
void Nasa9Poly1::modifyParameters(doublereal* coeffs)
{
    for (int i = 0; i < 9; i++) {
        m_coeff[i] = coeffs[i];
    }
}


}