CoolProp 7.2.0
An open-source fluid property and humid air property database
PCSAFTBackend.h
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1#ifndef PCSAFTBACKEND_H
2#define PCSAFTBACKEND_H
3
4#include "AbstractState.h"
5#include "CoolPropTools.h"
6#include "DataStructures.h"
7#include "PCSAFTLibrary.h"
8#include "Configuration.h"
9#include "Exceptions.h"
10#include <vector>
11
12using std::vector;
13
14namespace CoolProp {
15
16const static double kb = 1.380649e-23; // Boltzmann constant, J K^-1
17const static double PI = 3.141592653589793;
18const static double N_AV = 6.02214076e23; // Avagadro's number
19const static double E_CHRG = 1.6021766208e-19; // elementary charge, units of coulomb
20const static double perm_vac = 8.854187817e-22; //permittivity in vacuum, C V^-1 Angstrom^-1
21
22class PCSAFTBackend : public AbstractState
23{
24
25 protected:
26 std::vector<PCSAFTFluid> components;
27 std::vector<int> assoc_num;
28 std::vector<int>
29 assoc_matrix;
30 std::vector<double> k_ij;
31 std::vector<double> k_ijT;
32 bool is_pure_or_pseudopure;
33 std::vector<CoolPropDbl> mole_fractions;
34 std::vector<double> mole_fractions_double;
35 std::vector<CoolPropDbl> K,
36 lnK;
37 double dielc;
38
39 shared_ptr<PCSAFTBackend> SatL;
40 shared_ptr<PCSAFTBackend> SatV;
41
42 std::size_t N;
43
44 bool water_present;
45 int water_idx;
46 bool ion_term;
47 bool polar_term;
48 bool assoc_term;
49
50 void post_update(bool optional_checks = true);
51
52 CoolPropDbl solver_rho_Tp(CoolPropDbl T, CoolPropDbl p, phases phase);
53 double estimate_flash_p(PCSAFTBackend& PCSAFT);
54 double estimate_flash_t(PCSAFTBackend& PCSAFT);
55 double outerTQ(double p_guess, PCSAFTBackend& PCSAFT);
56 double outerPQ(double t_guess, PCSAFTBackend& PCSAFT);
57 phases calc_phase_internal(CoolProp::input_pairs input_pair);
58 CoolPropDbl reduced_to_molar(CoolPropDbl nu, CoolPropDbl T);
59
60 // these functions are used internally to solve for association parameters
61 vector<double> XA_find(vector<double> XA_guess, vector<double> delta_ij, double den, vector<double> x);
62 vector<double> dXAdx_find(vector<int> assoc_num, vector<double> delta_ij, double den, vector<double> XA, vector<double> ddelta_dx,
63 vector<double> x);
64 vector<double> dXAdt_find(vector<double> delta_ij, double den, vector<double> XA, vector<double> ddelta_dt, vector<double> x);
65 void set_assoc_matrix();
66 double dielc_water(double t);
67
68 public:
69 PCSAFTBackend(const std::vector<std::string>& component_names, bool generate_SatL_and_SatV = true);
70 PCSAFTBackend(const std::vector<PCSAFTFluid>& components, bool generate_SatL_and_SatV = true);
71 virtual PCSAFTBackend* get_copy(bool generate_SatL_and_SatV = true);
72
74 std::string backend_name(void) {
75 return get_backend_string(PCSAFT_BACKEND);
76 }
77
78 bool using_mole_fractions(void) {
79 return true;
80 };
81 bool using_mass_fractions(void) {
82 return false;
83 };
84 bool using_volu_fractions(void) {
85 return false;
86 };
87
88 void set_mass_fractions(const std::vector<CoolPropDbl>& mass_fractions);
89 void set_volu_fractions(const std::vector<CoolPropDbl>& volu_fractions) {
90 throw NotImplementedError("Volume composition has not been implemented.");
91 };
92 void set_mole_fractions(const std::vector<CoolPropDbl>& mole_fractions);
93 const std::vector<CoolPropDbl>& get_mole_fractions(void) {
94 return this->mole_fractions;
95 };
96
97 void resize(std::size_t N);
98
99 virtual void update(CoolProp::input_pairs input_pair, double value1, double value2); // %%checked
100
101 const double get_fluid_constant(std::size_t i, parameters param) const {
102 // const PCSAFTFluid &fld = components[i];
103 // switch(param){
104 // case im: return fld.m;
105 // case isigma: return fld.sigma;
106 // case iu: return fld.u;
107 // case iuAB: return fld.uAB;
108 // case ikappa: return fld.kappa;
109 // case idipm: return fld.dipm;
110 // case idipnum: return fld.dipnum;
111 // case iacentric_factor: return fld.EOS().acentric;
112 // case imolar_mass: return fld.EOS().molar_mass;
113 // default:
114 // throw ValueError(format("I don't know what to do with this fluid constant: %s", get_parameter_information(param,"short").c_str()));
115 // }
116 throw ValueError(format("I don't know what to do with this fluid constant: %s", get_parameter_information(param, "short").c_str()));
117 }
118
119 // ************************************************************************* //
120 // Basic Thermodynamic Functions //
121 // ************************************************************************* //
122 //
124 CoolPropDbl calc_pressure(void);
125
127 CoolPropDbl update_DmolarT(CoolPropDbl rho);
128
129 // CoolPropDbl calc_alpha0(void); // ideal gas helmholtz energy term
130 CoolPropDbl calc_alphar(void); // residual helmholtz energy
131 CoolPropDbl calc_dadt(void); // derivative of the residual helmholtz energy with respect to temperature
132 CoolPropDbl calc_hmolar_residual(void);
133 CoolPropDbl calc_smolar_residual(void);
134 vector<CoolPropDbl> calc_fugacity_coefficients(void);
135 CoolPropDbl calc_gibbsmolar_residual(void);
136 // CoolPropDbl calc_cpmolar(void); // TODO implement these heat capacity functions
137 // CoolPropDbl calc_cp0molar(void);
138 CoolPropDbl calc_compressibility_factor(void);
139
140 void flash_QT(PCSAFTBackend& PCSAFT);
141 void flash_PQ(PCSAFTBackend& PCSAFT);
142
143 phases calc_phase(void) {
144 return _phase;
145 };
150 void calc_specify_phase(phases phase_index) {
151 imposed_phase_index = phase_index;
152 _phase = phase_index;
153 }
156 void calc_unspecify_phase() {
157 imposed_phase_index = iphase_not_imposed;
158 }
159 //
160 // ************************************************************************* //
161 // Trivial Functions //
162 // ************************************************************************* //
163 //
164 double calc_molar_mass(void);
165 //
166};
167} /* namespace CoolProp */
168#endif /* PCSAFTBACKEND_H_ */
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