877 lines
27 KiB
C++
877 lines
27 KiB
C++
/**
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* @file MixtureFugacityTP.cpp
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* Methods file for a derived class of ThermoPhase that handles
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* non-ideal mixtures based on the fugacity models (see \ref thermoprops and
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* class \link Cantera::MixtureFugacityTP MixtureFugacityTP\endlink).
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*/
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/*
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* Copyright (2005) Sandia Corporation. Under the terms of
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* Contract DE-AC04-94AL85000 with Sandia Corporation, the
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* U.S. Government retains certain rights in this software.
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*/
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#include "cantera/thermo/MixtureFugacityTP.h"
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#include "cantera/base/stringUtils.h"
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#include "cantera/base/ctml.h"
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using namespace std;
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namespace Cantera
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{
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MixtureFugacityTP::MixtureFugacityTP() :
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m_Pcurrent(-1.0),
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iState_(FLUID_GAS),
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forcedState_(FLUID_UNDEFINED),
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m_Tlast_ref(-1.0)
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{
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}
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MixtureFugacityTP::MixtureFugacityTP(const MixtureFugacityTP& b) :
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m_Pcurrent(-1.0),
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iState_(FLUID_GAS),
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forcedState_(FLUID_UNDEFINED),
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m_Tlast_ref(-1.0)
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{
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MixtureFugacityTP::operator=(b);
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}
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MixtureFugacityTP& MixtureFugacityTP::operator=(const MixtureFugacityTP& b)
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{
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if (&b != this) {
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// Mostly, this is a passthrough to the underlying assignment operator
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// for the ThermoPhase parent object.
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ThermoPhase::operator=(b);
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// However, we have to handle data that we own.
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m_Pcurrent = b.m_Pcurrent;
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moleFractions_ = b.moleFractions_;
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iState_ = b.iState_;
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forcedState_ = b.forcedState_;
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m_Tlast_ref = b.m_Tlast_ref;
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m_h0_RT = b.m_h0_RT;
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m_cp0_R = b.m_cp0_R;
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m_g0_RT = b.m_g0_RT;
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m_s0_R = b.m_s0_R;
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}
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return *this;
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}
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ThermoPhase* MixtureFugacityTP::duplMyselfAsThermoPhase() const
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{
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return new MixtureFugacityTP(*this);
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}
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int MixtureFugacityTP::standardStateConvention() const
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{
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return cSS_CONVENTION_TEMPERATURE;
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}
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void MixtureFugacityTP::setForcedSolutionBranch(int solnBranch)
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{
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forcedState_ = solnBranch;
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}
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int MixtureFugacityTP::forcedSolutionBranch() const
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{
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return forcedState_;
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}
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int MixtureFugacityTP::reportSolnBranchActual() const
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{
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return iState_;
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}
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// ---- Partial Molar Properties of the Solution -----------------
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void MixtureFugacityTP::getChemPotentials_RT(doublereal* muRT) const
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{
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getChemPotentials(muRT);
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for (size_t k = 0; k < m_kk; k++) {
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muRT[k] *= 1.0 / RT();
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}
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}
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// ----- Thermodynamic Values for the Species Standard States States ----
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void MixtureFugacityTP::getStandardChemPotentials(doublereal* g) const
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{
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_updateReferenceStateThermo();
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copy(m_g0_RT.begin(), m_g0_RT.end(), g);
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double tmp = log(pressure() /m_spthermo->refPressure());
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for (size_t k = 0; k < m_kk; k++) {
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g[k] = RT() * (g[k] + tmp);
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}
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}
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void MixtureFugacityTP::getEnthalpy_RT(doublereal* hrt) const
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{
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getEnthalpy_RT_ref(hrt);
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}
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void MixtureFugacityTP::getEntropy_R(doublereal* sr) const
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{
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_updateReferenceStateThermo();
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copy(m_s0_R.begin(), m_s0_R.end(), sr);
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double tmp = log(pressure() /m_spthermo->refPressure());
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for (size_t k = 0; k < m_kk; k++) {
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sr[k] -= tmp;
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}
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}
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void MixtureFugacityTP::getGibbs_RT(doublereal* grt) const
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{
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_updateReferenceStateThermo();
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copy(m_g0_RT.begin(), m_g0_RT.end(), grt);
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double tmp = log(pressure() /m_spthermo->refPressure());
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for (size_t k = 0; k < m_kk; k++) {
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grt[k] += tmp;
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}
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}
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void MixtureFugacityTP::getPureGibbs(doublereal* g) const
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{
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_updateReferenceStateThermo();
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scale(m_g0_RT.begin(), m_g0_RT.end(), g, RT());
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double tmp = log(pressure() /m_spthermo->refPressure()) * RT();
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for (size_t k = 0; k < m_kk; k++) {
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g[k] += tmp;
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}
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}
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void MixtureFugacityTP::getIntEnergy_RT(doublereal* urt) const
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{
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_updateReferenceStateThermo();
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copy(m_h0_RT.begin(), m_h0_RT.end(), urt);
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for (size_t i = 0; i < m_kk; i++) {
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urt[i] -= 1.0;
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}
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}
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void MixtureFugacityTP::getCp_R(doublereal* cpr) const
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{
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_updateReferenceStateThermo();
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copy(m_cp0_R.begin(), m_cp0_R.end(), cpr);
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}
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void MixtureFugacityTP::getStandardVolumes(doublereal* vol) const
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{
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_updateReferenceStateThermo();
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for (size_t i = 0; i < m_kk; i++) {
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vol[i] = RT() / pressure();
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}
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}
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// ----- Thermodynamic Values for the Species Reference States ----
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void MixtureFugacityTP::getEnthalpy_RT_ref(doublereal* hrt) const
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{
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_updateReferenceStateThermo();
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copy(m_h0_RT.begin(), m_h0_RT.end(), hrt);
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}
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void MixtureFugacityTP::getGibbs_RT_ref(doublereal* grt) const
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{
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_updateReferenceStateThermo();
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copy(m_g0_RT.begin(), m_g0_RT.end(), grt);
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}
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void MixtureFugacityTP::getGibbs_ref(doublereal* g) const
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{
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const vector_fp& gibbsrt = gibbs_RT_ref();
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scale(gibbsrt.begin(), gibbsrt.end(), g, RT());
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}
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const vector_fp& MixtureFugacityTP::gibbs_RT_ref() const
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{
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_updateReferenceStateThermo();
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return m_g0_RT;
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}
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void MixtureFugacityTP::getEntropy_R_ref(doublereal* er) const
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{
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_updateReferenceStateThermo();
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copy(m_s0_R.begin(), m_s0_R.end(), er);
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}
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void MixtureFugacityTP::getCp_R_ref(doublereal* cpr) const
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{
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_updateReferenceStateThermo();
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copy(m_cp0_R.begin(), m_cp0_R.end(), cpr);
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}
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void MixtureFugacityTP::getStandardVolumes_ref(doublereal* vol) const
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{
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_updateReferenceStateThermo();
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for (size_t i = 0; i < m_kk; i++) {
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vol[i]= RT() / refPressure();
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}
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}
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void MixtureFugacityTP::setStateFromXML(const XML_Node& state)
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{
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int doTP = 0;
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string comp = getChildValue(state,"moleFractions");
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if (comp != "") {
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// not overloaded in current object -> phase state is not calculated.
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setMoleFractionsByName(comp);
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doTP = 1;
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} else {
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comp = getChildValue(state,"massFractions");
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if (comp != "") {
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// not overloaded in current object -> phase state is not calculated.
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setMassFractionsByName(comp);
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doTP = 1;
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}
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}
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double t = temperature();
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if (state.hasChild("temperature")) {
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t = getFloat(state, "temperature", "temperature");
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doTP = 1;
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}
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if (state.hasChild("pressure")) {
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double p = getFloat(state, "pressure", "pressure");
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setState_TP(t, p);
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} else if (state.hasChild("density")) {
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double rho = getFloat(state, "density", "density");
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setState_TR(t, rho);
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} else if (doTP) {
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double rho = Phase::density();
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setState_TR(t, rho);
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}
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}
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bool MixtureFugacityTP::addSpecies(shared_ptr<Species> spec)
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{
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bool added = ThermoPhase::addSpecies(spec);
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if (added) {
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if (m_kk == 1) {
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moleFractions_.push_back(1.0);
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} else {
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moleFractions_.push_back(0.0);
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}
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m_h0_RT.push_back(0.0);
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m_cp0_R.push_back(0.0);
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m_g0_RT.push_back(0.0);
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m_s0_R.push_back(0.0);
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}
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return added;
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}
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void MixtureFugacityTP::setTemperature(const doublereal temp)
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{
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_updateReferenceStateThermo();
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setState_TR(temperature(), density());
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}
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void MixtureFugacityTP::setPressure(doublereal p)
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{
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setState_TP(temperature(), p);
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}
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void MixtureFugacityTP::compositionChanged()
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{
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Phase::compositionChanged();
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getMoleFractions(moleFractions_.data());
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}
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void MixtureFugacityTP::setMoleFractions_NoState(const doublereal* const x)
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{
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Phase::setMoleFractions(x);
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getMoleFractions(moleFractions_.data());
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updateMixingExpressions();
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}
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void MixtureFugacityTP::calcDensity()
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{
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throw NotImplementedError("MixtureFugacityTP::calcDensity() "
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"called, but EOS for phase is not known");
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}
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void MixtureFugacityTP::setState_TP(doublereal t, doublereal pres)
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{
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// A pretty tricky algorithm is needed here, due to problems involving
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// standard states of real fluids. For those cases you need to combine the T
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// and P specification for the standard state, or else you may venture into
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// the forbidden zone, especially when nearing the triple point. Therefore,
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// we need to do the standard state thermo calc with the (t, pres) combo.
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getMoleFractions(moleFractions_.data());
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Phase::setTemperature(t);
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_updateReferenceStateThermo();
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// Depends on the mole fractions and the temperature
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updateMixingExpressions();
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m_Pcurrent = pres;
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if (forcedState_ == FLUID_UNDEFINED) {
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double rhoNow = Phase::density();
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double rho = densityCalc(t, pres, iState_, rhoNow);
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if (rho > 0.0) {
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Phase::setDensity(rho);
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m_Pcurrent = pres;
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iState_ = phaseState(true);
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} else {
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if (rho < -1.5) {
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rho = densityCalc(t, pres, FLUID_UNDEFINED , rhoNow);
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if (rho > 0.0) {
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Phase::setDensity(rho);
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m_Pcurrent = pres;
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iState_ = phaseState(true);
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} else {
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throw CanteraError("MixtureFugacityTP::setState_TP()", "neg rho");
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}
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} else {
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throw CanteraError("MixtureFugacityTP::setState_TP()", "neg rho");
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}
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}
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} else if (forcedState_ == FLUID_GAS) {
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// Normal density calculation
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if (iState_ < FLUID_LIQUID_0) {
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double rhoNow = Phase::density();
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double rho = densityCalc(t, pres, iState_, rhoNow);
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if (rho > 0.0) {
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Phase::setDensity(rho);
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m_Pcurrent = pres;
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iState_ = phaseState(true);
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if (iState_ >= FLUID_LIQUID_0) {
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throw CanteraError("MixtureFugacityTP::setState_TP()", "wrong state");
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}
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} else {
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throw CanteraError("MixtureFugacityTP::setState_TP()", "neg rho");
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}
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}
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} else if (forcedState_ > FLUID_LIQUID_0) {
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if (iState_ >= FLUID_LIQUID_0) {
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double rhoNow = Phase::density();
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double rho = densityCalc(t, pres, iState_, rhoNow);
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if (rho > 0.0) {
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Phase::setDensity(rho);
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m_Pcurrent = pres;
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iState_ = phaseState(true);
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if (iState_ == FLUID_GAS) {
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throw CanteraError("MixtureFugacityTP::setState_TP()", "wrong state");
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}
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} else {
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throw CanteraError("MixtureFugacityTP::setState_TP()", "neg rho");
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}
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}
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}
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}
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void MixtureFugacityTP::setState_TR(doublereal T, doublereal rho)
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{
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getMoleFractions(moleFractions_.data());
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Phase::setTemperature(T);
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_updateReferenceStateThermo();
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Phase::setDensity(rho);
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doublereal mv = molarVolume();
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// depends on mole fraction and temperature
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updateMixingExpressions();
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m_Pcurrent = pressureCalc(T, mv);
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iState_ = phaseState(true);
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}
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void MixtureFugacityTP::setState_TPX(doublereal t, doublereal p, const doublereal* x)
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{
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setMoleFractions_NoState(x);
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setState_TP(t,p);
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}
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doublereal MixtureFugacityTP::z() const
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{
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return pressure() * meanMolecularWeight() / (density() * RT());
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}
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doublereal MixtureFugacityTP::sresid() const
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{
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throw CanteraError("MixtureFugacityTP::sresid()", "Base Class: not implemented");
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}
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doublereal MixtureFugacityTP::hresid() const
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{
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throw CanteraError("MixtureFugacityTP::hresid()", "Base Class: not implemented");
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}
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doublereal MixtureFugacityTP::psatEst(doublereal TKelvin) const
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{
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doublereal pcrit = critPressure();
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doublereal tt = critTemperature() / TKelvin;
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if (tt < 1.0) {
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return pcrit;
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}
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doublereal lpr = -0.8734*tt*tt - 3.4522*tt + 4.2918;
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return pcrit*exp(lpr);
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}
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doublereal MixtureFugacityTP::liquidVolEst(doublereal TKelvin, doublereal& pres) const
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{
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throw CanteraError("MixtureFugacityTP::liquidVolEst()", "unimplemented");
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}
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doublereal MixtureFugacityTP::densityCalc(doublereal TKelvin, doublereal presPa,
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int phase, doublereal rhoguess)
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{
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doublereal tcrit = critTemperature();
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doublereal mmw = meanMolecularWeight();
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if (rhoguess == -1.0) {
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if (phase != -1) {
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if (TKelvin > tcrit) {
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rhoguess = presPa * mmw / (GasConstant * TKelvin);
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} else {
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if (phase == FLUID_GAS || phase == FLUID_SUPERCRIT) {
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rhoguess = presPa * mmw / (GasConstant * TKelvin);
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} else if (phase >= FLUID_LIQUID_0) {
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double lqvol = liquidVolEst(TKelvin, presPa);
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rhoguess = mmw / lqvol;
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}
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}
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} else {
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// Assume the Gas phase initial guess, if nothing is specified to
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// the routine
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rhoguess = presPa * mmw / (GasConstant * TKelvin);
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}
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}
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double molarVolBase = mmw / rhoguess;
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double molarVolLast = molarVolBase;
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double vc = mmw / critDensity();
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// molar volume of the spinodal at the current temperature and mole
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// fractions. this will be updated as we go.
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double molarVolSpinodal = vc;
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bool conv = false;
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// We start on one side of the vc and stick with that side
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bool gasSide = molarVolBase > vc;
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if (gasSide) {
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molarVolLast = (GasConstant * TKelvin)/presPa;
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} else {
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molarVolLast = liquidVolEst(TKelvin, presPa);
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}
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// OK, now we do a small solve to calculate the molar volume given the T,P
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// value. The algorithm is taken from dfind()
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for (int n = 0; n < 200; n++) {
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// Calculate the predicted reduced pressure, pred0, based on the current
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// tau and dd. Calculate the derivative of the predicted pressure wrt
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// the molar volume. This routine also returns the pressure, presBase
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double presBase;
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double dpdVBase = dpdVCalc(TKelvin, molarVolBase, presBase);
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// If dpdV is positive, then we are in the middle of the 2 phase region
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// and beyond the spinodal stability curve. We need to adjust the
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// initial guess outwards and start a new iteration.
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if (dpdVBase >= 0.0) {
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if (TKelvin > tcrit) {
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throw CanteraError("MixtureFugacityTP::densityCalc",
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"T > tcrit unexpectedly");
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}
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// TODO Spawn a calculation for the value of the spinodal point that
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// is very accurate. Answer the question as to whether a
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// solution is possible on the current side of the vapor dome.
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if (gasSide) {
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if (molarVolBase >= vc) {
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molarVolSpinodal = molarVolBase;
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molarVolBase = 0.5 * (molarVolLast + molarVolSpinodal);
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} else {
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molarVolBase = 0.5 * (molarVolLast + molarVolSpinodal);
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}
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} else {
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if (molarVolBase <= vc) {
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molarVolSpinodal = molarVolBase;
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molarVolBase = 0.5 * (molarVolLast + molarVolSpinodal);
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} else {
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molarVolBase = 0.5 * (molarVolLast + molarVolSpinodal);
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}
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}
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continue;
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}
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// Check for convergence
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if (fabs(presBase-presPa) < 1.0E-30 + 1.0E-8 * presPa) {
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conv = true;
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break;
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}
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// Dampen and crop the update
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doublereal dpdV = dpdVBase;
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if (n < 10) {
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dpdV = dpdVBase * 1.5;
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}
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// Formulate the update to the molar volume by Newton's method. Then,
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// crop it to a max value of 0.1 times the current volume
|
|
double delMV = - (presBase - presPa) / dpdV;
|
|
if ((!gasSide || delMV < 0.0) && fabs(delMV) > 0.2 * molarVolBase) {
|
|
delMV = delMV / fabs(delMV) * 0.2 * molarVolBase;
|
|
}
|
|
// Only go 1/10 the way towards the spinodal at any one time.
|
|
if (TKelvin < tcrit) {
|
|
if (gasSide) {
|
|
if (delMV < 0.0 && -delMV > 0.5 * (molarVolBase - molarVolSpinodal)) {
|
|
delMV = - 0.5 * (molarVolBase - molarVolSpinodal);
|
|
}
|
|
} else {
|
|
if (delMV > 0.0 && delMV > 0.5 * (molarVolSpinodal - molarVolBase)) {
|
|
delMV = 0.5 * (molarVolSpinodal - molarVolBase);
|
|
}
|
|
}
|
|
}
|
|
// updated the molar volume value
|
|
molarVolLast = molarVolBase;
|
|
molarVolBase += delMV;
|
|
|
|
if (fabs(delMV/molarVolBase) < 1.0E-14) {
|
|
conv = true;
|
|
break;
|
|
}
|
|
|
|
// Check for negative molar volumes
|
|
if (molarVolBase <= 0.0) {
|
|
molarVolBase = std::min(1.0E-30, fabs(delMV*1.0E-4));
|
|
}
|
|
}
|
|
|
|
// Check for convergence, and return 0.0 if it wasn't achieved.
|
|
double densBase = 0.0;
|
|
if (! conv) {
|
|
molarVolBase = 0.0;
|
|
throw CanteraError("MixtureFugacityTP::densityCalc()", "Process did not converge");
|
|
} else {
|
|
densBase = mmw / molarVolBase;
|
|
}
|
|
return densBase;
|
|
}
|
|
|
|
void MixtureFugacityTP::updateMixingExpressions()
|
|
{
|
|
}
|
|
|
|
MixtureFugacityTP::spinodalFunc::spinodalFunc(MixtureFugacityTP* tp) :
|
|
m_tp(tp)
|
|
{
|
|
}
|
|
|
|
int MixtureFugacityTP::spinodalFunc::evalSS(const doublereal t, const doublereal* const y,
|
|
doublereal* const r)
|
|
{
|
|
doublereal molarVol = y[0];
|
|
doublereal pp;
|
|
r[0] = m_tp->dpdVCalc(m_tp->temperature(), molarVol, pp);
|
|
return 0;
|
|
}
|
|
|
|
int MixtureFugacityTP::corr0(doublereal TKelvin, doublereal pres, doublereal& densLiqGuess,
|
|
doublereal& densGasGuess, doublereal& liqGRT, doublereal& gasGRT)
|
|
{
|
|
int retn = 0;
|
|
doublereal densLiq = densityCalc(TKelvin, pres, FLUID_LIQUID_0, densLiqGuess);
|
|
if (densLiq <= 0.0) {
|
|
retn = -1;
|
|
} else {
|
|
densLiqGuess = densLiq;
|
|
setState_TR(TKelvin, densLiq);
|
|
liqGRT = gibbs_mole() / RT();
|
|
}
|
|
|
|
doublereal densGas = densityCalc(TKelvin, pres, FLUID_GAS, densGasGuess);
|
|
if (densGas <= 0.0) {
|
|
if (retn == -1) {
|
|
throw CanteraError("MixtureFugacityTP::corr0",
|
|
"Error occurred trying to find gas density at (T,P) = {} {}",
|
|
TKelvin, pres);
|
|
}
|
|
retn = -2;
|
|
} else {
|
|
densGasGuess = densGas;
|
|
setState_TR(TKelvin, densGas);
|
|
gasGRT = gibbs_mole() / RT();
|
|
}
|
|
return retn;
|
|
}
|
|
|
|
int MixtureFugacityTP::phaseState(bool checkState) const
|
|
{
|
|
int state = iState_;
|
|
if (checkState) {
|
|
double t = temperature();
|
|
double tcrit = critTemperature();
|
|
double rhocrit = critDensity();
|
|
if (t >= tcrit) {
|
|
return FLUID_SUPERCRIT;
|
|
}
|
|
double tmid = tcrit - 100.;
|
|
if (tmid < 0.0) {
|
|
tmid = tcrit / 2.0;
|
|
}
|
|
double pp = psatEst(tmid);
|
|
double mmw = meanMolecularWeight();
|
|
double molVolLiqTmid = liquidVolEst(tmid, pp);
|
|
double molVolGasTmid = GasConstant * tmid / pp;
|
|
double densLiqTmid = mmw / molVolLiqTmid;
|
|
double densGasTmid = mmw / molVolGasTmid;
|
|
double densMidTmid = 0.5 * (densLiqTmid + densGasTmid);
|
|
doublereal rhoMid = rhocrit + (t - tcrit) * (rhocrit - densMidTmid) / (tcrit - tmid);
|
|
|
|
double rho = density();
|
|
int iStateGuess = FLUID_LIQUID_0;
|
|
if (rho < rhoMid) {
|
|
iStateGuess = FLUID_GAS;
|
|
}
|
|
double molarVol = mmw / rho;
|
|
double presCalc;
|
|
|
|
double dpdv = dpdVCalc(t, molarVol, presCalc);
|
|
if (dpdv < 0.0) {
|
|
state = iStateGuess;
|
|
} else {
|
|
state = FLUID_UNSTABLE;
|
|
}
|
|
}
|
|
return state;
|
|
}
|
|
|
|
doublereal MixtureFugacityTP::densSpinodalLiquid() const
|
|
{
|
|
throw CanteraError("MixtureFugacityTP::densSpinodalLiquid", "unimplemented");
|
|
}
|
|
|
|
doublereal MixtureFugacityTP::densSpinodalGas() const
|
|
{
|
|
throw CanteraError("MixtureFugacityTP::densSpinodalGas", "unimplemented");
|
|
}
|
|
|
|
doublereal MixtureFugacityTP::satPressure(doublereal TKelvin)
|
|
{
|
|
doublereal molarVolGas;
|
|
doublereal molarVolLiquid;
|
|
return calculatePsat(TKelvin, molarVolGas, molarVolLiquid);
|
|
}
|
|
|
|
doublereal MixtureFugacityTP::calculatePsat(doublereal TKelvin, doublereal& molarVolGas,
|
|
doublereal& molarVolLiquid)
|
|
{
|
|
// The algorithm for this routine has undergone quite a bit of work. It
|
|
// probably needs more work. However, it seems now to be fairly robust. The
|
|
// key requirement is to find an initial pressure where both the liquid and
|
|
// the gas exist. This is not as easy as it sounds, and it gets exceedingly
|
|
// hard as the critical temperature is approached from below. Once we have
|
|
// this initial state, then we seek to equilibrate the Gibbs free energies
|
|
// of the gas and liquid and use the formula
|
|
//
|
|
// dp = VdG
|
|
//
|
|
// to create an update condition for deltaP using
|
|
//
|
|
// - (Gliq - Ggas) = (Vliq - Vgas) (deltaP)
|
|
//
|
|
// @TODO Suggestions for the future would be to switch it to an algorithm
|
|
// that uses the gas molar volume and the liquid molar volumes as the
|
|
// fundamental unknowns.
|
|
|
|
// we need this because this is a non-const routine that is public
|
|
setTemperature(TKelvin);
|
|
double densSave = density();
|
|
double tempSave = temperature();
|
|
double pres;
|
|
doublereal mw = meanMolecularWeight();
|
|
if (TKelvin < critTemperature()) {
|
|
pres = psatEst(TKelvin);
|
|
// trial value = Psat from correlation
|
|
doublereal volLiquid = liquidVolEst(TKelvin, pres);
|
|
double RhoLiquidGood = mw / volLiquid;
|
|
double RhoGasGood = pres * mw / (GasConstant * TKelvin);
|
|
doublereal delGRT = 1.0E6;
|
|
doublereal liqGRT, gasGRT;
|
|
|
|
// First part of the calculation involves finding a pressure at which
|
|
// the gas and the liquid state coexists.
|
|
doublereal presLiquid = 0.;
|
|
doublereal presGas;
|
|
doublereal presBase = pres;
|
|
bool foundLiquid = false;
|
|
bool foundGas = false;
|
|
|
|
doublereal densLiquid = densityCalc(TKelvin, presBase, FLUID_LIQUID_0, RhoLiquidGood);
|
|
if (densLiquid > 0.0) {
|
|
foundLiquid = true;
|
|
presLiquid = pres;
|
|
RhoLiquidGood = densLiquid;
|
|
}
|
|
if (!foundLiquid) {
|
|
for (int i = 0; i < 50; i++) {
|
|
pres = 1.1 * pres;
|
|
densLiquid = densityCalc(TKelvin, pres, FLUID_LIQUID_0, RhoLiquidGood);
|
|
if (densLiquid > 0.0) {
|
|
foundLiquid = true;
|
|
presLiquid = pres;
|
|
RhoLiquidGood = densLiquid;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
pres = presBase;
|
|
doublereal densGas = densityCalc(TKelvin, pres, FLUID_GAS, RhoGasGood);
|
|
if (densGas <= 0.0) {
|
|
foundGas = false;
|
|
} else {
|
|
foundGas = true;
|
|
presGas = pres;
|
|
RhoGasGood = densGas;
|
|
}
|
|
if (!foundGas) {
|
|
for (int i = 0; i < 50; i++) {
|
|
pres = 0.9 * pres;
|
|
densGas = densityCalc(TKelvin, pres, FLUID_GAS, RhoGasGood);
|
|
if (densGas > 0.0) {
|
|
foundGas = true;
|
|
presGas = pres;
|
|
RhoGasGood = densGas;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (foundGas && foundLiquid && presGas != presLiquid) {
|
|
pres = 0.5 * (presLiquid + presGas);
|
|
bool goodLiq;
|
|
bool goodGas;
|
|
for (int i = 0; i < 50; i++) {
|
|
densLiquid = densityCalc(TKelvin, pres, FLUID_LIQUID_0, RhoLiquidGood);
|
|
if (densLiquid <= 0.0) {
|
|
goodLiq = false;
|
|
} else {
|
|
goodLiq = true;
|
|
RhoLiquidGood = densLiquid;
|
|
presLiquid = pres;
|
|
}
|
|
densGas = densityCalc(TKelvin, pres, FLUID_GAS, RhoGasGood);
|
|
if (densGas <= 0.0) {
|
|
goodGas = false;
|
|
} else {
|
|
goodGas = true;
|
|
RhoGasGood = densGas;
|
|
presGas = pres;
|
|
}
|
|
if (goodGas && goodLiq) {
|
|
break;
|
|
}
|
|
if (!goodLiq && !goodGas) {
|
|
pres = 0.5 * (pres + presLiquid);
|
|
}
|
|
if (goodLiq || goodGas) {
|
|
pres = 0.5 * (presLiquid + presGas);
|
|
}
|
|
}
|
|
}
|
|
if (!foundGas || !foundLiquid) {
|
|
writelog("error couldn't find a starting pressure\n");
|
|
return 0.0;
|
|
}
|
|
if (presGas != presLiquid) {
|
|
writelog("error couldn't find a starting pressure\n");
|
|
return 0.0;
|
|
}
|
|
|
|
pres = presGas;
|
|
double presLast = pres;
|
|
double RhoGas = RhoGasGood;
|
|
double RhoLiquid = RhoLiquidGood;
|
|
|
|
// Now that we have found a good pressure we can proceed with the algorithm.
|
|
for (int i = 0; i < 20; i++) {
|
|
int stab = corr0(TKelvin, pres, RhoLiquid, RhoGas, liqGRT, gasGRT);
|
|
if (stab == 0) {
|
|
presLast = pres;
|
|
delGRT = liqGRT - gasGRT;
|
|
doublereal delV = mw * (1.0/RhoLiquid - 1.0/RhoGas);
|
|
doublereal dp = - delGRT * GasConstant * TKelvin / delV;
|
|
|
|
if (fabs(dp) > 0.1 * pres) {
|
|
if (dp > 0.0) {
|
|
dp = 0.1 * pres;
|
|
} else {
|
|
dp = -0.1 * pres;
|
|
}
|
|
}
|
|
pres += dp;
|
|
} else if (stab == -1) {
|
|
delGRT = 1.0E6;
|
|
if (presLast > pres) {
|
|
pres = 0.5 * (presLast + pres);
|
|
} else {
|
|
// we are stuck here - try this
|
|
pres = 1.1 * pres;
|
|
}
|
|
} else if (stab == -2) {
|
|
if (presLast < pres) {
|
|
pres = 0.5 * (presLast + pres);
|
|
} else {
|
|
// we are stuck here - try this
|
|
pres = 0.9 * pres;
|
|
}
|
|
}
|
|
molarVolGas = mw / RhoGas;
|
|
molarVolLiquid = mw / RhoLiquid;
|
|
|
|
if (fabs(delGRT) < 1.0E-8) {
|
|
// converged
|
|
break;
|
|
}
|
|
}
|
|
|
|
molarVolGas = mw / RhoGas;
|
|
molarVolLiquid = mw / RhoLiquid;
|
|
// Put the fluid in the desired end condition
|
|
setState_TR(tempSave, densSave);
|
|
return pres;
|
|
} else {
|
|
pres = critPressure();
|
|
setState_TP(TKelvin, pres);
|
|
molarVolGas = mw / density();
|
|
molarVolLiquid = molarVolGas;
|
|
setState_TR(tempSave, densSave);
|
|
}
|
|
return pres;
|
|
}
|
|
|
|
doublereal MixtureFugacityTP::pressureCalc(doublereal TKelvin, doublereal molarVol) const
|
|
{
|
|
throw CanteraError("MixtureFugacityTP::pressureCalc", "unimplemented");
|
|
}
|
|
|
|
doublereal MixtureFugacityTP::dpdVCalc(doublereal TKelvin, doublereal molarVol, doublereal& presCalc) const
|
|
{
|
|
throw CanteraError("MixtureFugacityTP::dpdVCalc", "unimplemented");
|
|
}
|
|
|
|
void MixtureFugacityTP::_updateReferenceStateThermo() const
|
|
{
|
|
double Tnow = temperature();
|
|
|
|
// If the temperature has changed since the last time these
|
|
// properties were computed, recompute them.
|
|
if (m_Tlast_ref != Tnow) {
|
|
m_spthermo->update(Tnow, &m_cp0_R[0], &m_h0_RT[0], &m_s0_R[0]);
|
|
m_Tlast_ref = Tnow;
|
|
|
|
// update the species Gibbs functions
|
|
for (size_t k = 0; k < m_kk; k++) {
|
|
m_g0_RT[k] = m_h0_RT[k] - m_s0_R[k];
|
|
}
|
|
doublereal pref = refPressure();
|
|
if (pref <= 0.0) {
|
|
throw CanteraError("MixtureFugacityTP::_updateReferenceStateThermo()", "neg ref pressure");
|
|
}
|
|
}
|
|
}
|
|
|
|
void MixtureFugacityTP::invalidateCache()
|
|
{
|
|
ThermoPhase::invalidateCache();
|
|
m_Tlast_ref += 0.001234;
|
|
}
|
|
|
|
}
|