void ThermoPhase::getdlnActCoeffdlnN_numderiv(const size_t ld, doublereal* const dlnActCoeffdlnN)
{
double deltaMoles_j = 0.0;
double pres = pressure();
// Evaluate the current base activity coefficients if necessary
vector_fp ActCoeff_Base(m_kk);
getActivityCoefficients(ActCoeff_Base.data());
vector_fp Xmol_Base(m_kk);
getMoleFractions(Xmol_Base.data());
// Make copies of ActCoeff and Xmol_ for use in taking differences
vector_fp ActCoeff(m_kk);
vector_fp Xmol(m_kk);
double v_totalMoles = 1.0;
double TMoles_base = v_totalMoles;
// Loop over the columns species to be deltad
for (size_t j = 0; j < m_kk; j++) {
// Calculate a value for the delta moles of species j
// -> Note Xmol_[] and Tmoles are always positive or zero quantities.
// -> experience has shown that you always need to make the deltas
// greater than needed to change the other mole fractions in order
// to capture some effects.
double moles_j_base = v_totalMoles * Xmol_Base[j];
deltaMoles_j = 1.0E-7 * moles_j_base + v_totalMoles * 1.0E-13 + 1.0E-150;
// Now, update the total moles in the phase and all of the mole
// fractions based on this.
v_totalMoles = TMoles_base + deltaMoles_j;
for (size_t k = 0; k < m_kk; k++) {
Xmol[k] = Xmol_Base[k] * TMoles_base / v_totalMoles;
}
Xmol[j] = (moles_j_base + deltaMoles_j) / v_totalMoles;
// Go get new values for the activity coefficients.
// -> Note this calls setState_PX();
setState_PX(pres, Xmol.data());
getActivityCoefficients(ActCoeff.data());
// Calculate the column of the matrix
double* const lnActCoeffCol = dlnActCoeffdlnN + ld * j;
for (size_t k = 0; k < m_kk; k++) {
lnActCoeffCol[k] = (2*moles_j_base + deltaMoles_j) *(ActCoeff[k] - ActCoeff_Base[k]) /
((ActCoeff[k] + ActCoeff_Base[k]) * deltaMoles_j);
}
// Revert to the base case Xmol_, v_totalMoles
v_totalMoles = TMoles_base;
Xmol = Xmol_Base;
}
setState_PX(pres, Xmol_Base.data());
}
void vcs_VolPhase::_updateLnActCoeffJac()
{
double phaseTotalMoles = v_totalMoles;
if (phaseTotalMoles < 1.0E-14) {
phaseTotalMoles = 1.0;
}
/*
* Evaluate the current base activity coefficients if necessary
*/
if (!m_UpToDate_AC) {
_updateActCoeff();
}
if (!TP_ptr) {
return;
}
TP_ptr->getdlnActCoeffdlnN(m_numSpecies, &np_dLnActCoeffdMolNumber(0,0));
for (size_t j = 0; j < m_numSpecies; j++) {
double moles_j_base = phaseTotalMoles * Xmol_[j];
double* const np_lnActCoeffCol = np_dLnActCoeffdMolNumber.ptrColumn(j);
if (moles_j_base < 1.0E-200) {
moles_j_base = 1.0E-7 * moles_j_base + 1.0E-13 * phaseTotalMoles + 1.0E-150;
}
for (size_t k = 0; k < m_numSpecies; k++) {
np_lnActCoeffCol[k] = np_lnActCoeffCol[k] * phaseTotalMoles / moles_j_base;
}
}
double deltaMoles_j = 0.0;
// Make copies of ActCoeff and Xmol_ for use in taking differences
std::vector<double> ActCoeff_Base(ActCoeff);
std::vector<double> Xmol_Base(Xmol_);
double TMoles_base = phaseTotalMoles;
/*
* Loop over the columns species to be deltad
*/
for (size_t j = 0; j < m_numSpecies; j++) {
/*
* Calculate a value for the delta moles of species j
* -> Note Xmol_[] and Tmoles are always positive or zero
* quantities.
*/
double moles_j_base = phaseTotalMoles * Xmol_Base[j];
deltaMoles_j = 1.0E-7 * moles_j_base + 1.0E-13 * phaseTotalMoles + 1.0E-150;
/*
* Now, update the total moles in the phase and all of the
* mole fractions based on this.
*/
phaseTotalMoles = TMoles_base + deltaMoles_j;
for (size_t k = 0; k < m_numSpecies; k++) {
Xmol_[k] = Xmol_Base[k] * TMoles_base / phaseTotalMoles;
}
Xmol_[j] = (moles_j_base + deltaMoles_j) / phaseTotalMoles;
/*
* Go get new values for the activity coefficients.
* -> Note this calls setState_PX();
*/
_updateMoleFractionDependencies();
_updateActCoeff();
/*
* Revert to the base case Xmol_, v_totalMoles
*/
v_totalMoles = TMoles_base;
Xmol_ = Xmol_Base;
}
/*
* Go get base values for the activity coefficients.
* -> Note this calls setState_TPX() again;
* -> Just wanted to make sure that cantera is in sync
* with VolPhase after this call.
*/
setMoleFractions(VCS_DATA_PTR(Xmol_Base));
_updateMoleFractionDependencies();
_updateActCoeff();
}
