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n-Propane viscosity can mostly be read from JSON, all that remains is the higher order terms, some thinking remains on that front

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Signed-off-by: Ian bell <ian.h.bell@gmail.com>
This commit is contained in:
Ian bell
2014-05-20 16:27:23 +02:00
parent f12c749914
commit 04db9963f0
4 changed files with 128 additions and 27 deletions
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60
src/Backends/Helmholtz/Fluids/FluidLibrary.h
View File

@@ -257,6 +257,57 @@ protected:
fluid.pEOS = &(fluid.EOSVector[0]);
};
/// Parse the transport properties
void parse_dilute_viscosity(rapidjson::Value &dilute, CoolPropFluid & fluid)
{
std::string type = cpjson::get_string(dilute, "type");
if (!type.compare("collision_integral")){
// Get a reference to the entry in the fluid instance
CoolProp::ViscosityDiluteGasCollisionIntegralData &CI = fluid.transport.viscosity_dilute.collision_integral;
// Load up the values
CI.a = cpjson::get_long_double_array(dilute["a"]);
CI.t = cpjson::get_long_double_array(dilute["t"]);
CI.molar_mass = cpjson::get_double(dilute, "molar_mass");
CI.C = cpjson::get_double(dilute, "C");
}
else{
throw ValueError(format("type [%s] is not understood for fluid %s",type.c_str(),fluid.name.c_str()));
}
};
/// Parse the transport properties
void parse_initial_density_viscosity(rapidjson::Value &dilute, CoolPropFluid & fluid)
{
std::string type = cpjson::get_string(dilute, "type");
if (!type.compare("Rainwater-Friend")){
// Get a reference to the entry in the fluid instance
CoolProp::ViscosityRainWaterFriendData &RF = fluid.transport.viscosity_initial.rainwater_friend;
// Load up the values
RF.b = cpjson::get_long_double_array(dilute["b"]);
RF.t = cpjson::get_long_double_array(dilute["t"]);
}
else{
throw ValueError(format("type [%s] is not understood for fluid %s",type.c_str(),fluid.name.c_str()));
}
};
/// Parse the transport properties
void parse_viscosity(rapidjson::Value &viscosity, CoolPropFluid & fluid)
{
if (viscosity.HasMember("dilute")){
parse_dilute_viscosity(viscosity["dilute"], fluid);
}
if (viscosity.HasMember("initial_density")){
parse_initial_density_viscosity(viscosity["initial_density"], fluid);
}
};
/// Parse the thermal conductivity data
void parse_thermal_conductivity(rapidjson::Value &conductivity, CoolPropFluid & fluid)
{
};
/// Parse the transport properties
void parse_transport(rapidjson::Value &transport, CoolPropFluid & fluid)
{
@@ -267,6 +318,15 @@ protected:
fluid.transport.sigma_eta = cpjson::get_double(transport, "sigma_eta");
fluid.transport.epsilon_over_k = cpjson::get_double(transport, "epsilon_over_k");
}
// Parse viscosity
if (transport.HasMember("viscosity")){
parse_viscosity(transport["viscosity"],fluid);
}
// Parse thermal conductivity
if (transport.HasMember("conductivity")){
parse_thermal_conductivity(transport["conductivity"],fluid);
}
};
void default_transport(CoolPropFluid & fluid)

42
src/Backends/Helmholtz/TransportRoutines.cpp
View File

@@ -1,5 +1,6 @@
#include "TransportRoutines.h"
#include "CoolPropFluid.h"
namespace CoolProp{
@@ -20,28 +21,24 @@ long double TransportRoutines::general_dilute_gas_viscosity(HelmholtzEOSMixtureB
return 26.692e-9*sqrt(molar_mass_kgkmol*HEOS.T())/(pow(sigma_nm, 2)*OMEGA22); // Pa-s
}
else{
throw NotImplementedError("TransportRoutines::GeneralDiluteGasViscosity is only for pure and pseudo-pure");
throw NotImplementedError("TransportRoutines::general_dilute_gas_viscosity is only for pure and pseudo-pure");
}
}
long double TransportRoutines::dilute_gas_viscosity(HelmholtzEOSMixtureBackend &HEOS)
{
if (HEOS.is_pure_or_pseudopure)
{
// HARD CODED FOR PROPANE FOR TESTING PURPOSES
double _a[]={0.25104574,-0.47271238,0,0.060836515}, _t[] = {0,1,2,3}, C = 0.141824e-6/sqrt(44.0956), D = sqrt(44.0956)*C;
std::vector<long double> a(_a,_a+sizeof(_a)/sizeof(_a[0]));
std::vector<long double> t(_t,_t+sizeof(_t)/sizeof(_t[0]));
HEOS.components[0]->transport.epsilon_over_k = 263.88;
HEOS.components[0]->transport.sigma_eta = 0.49748e-9;
long double molar_mass = 44.0956/1000;
// Retrieve values from the state class
CoolProp::ViscosityDiluteGasCollisionIntegralData &data = HEOS.components[0]->transport.viscosity_dilute.collision_integral;
const std::vector<long double> &a = data.a, &t = data.t;
const long double C = data.C, molar_mass = data.molar_mass;
long double S;
long double Tstar = HEOS.T()/HEOS.components[0]->transport.epsilon_over_k;
long double sigma_nm = HEOS.components[0]->transport.sigma_eta*1e9; // 1e9 to convert from m to nm
long double molar_mass_kgkmol = molar_mass*1000; // 1000 to convert from kg/mol to kg/kmol
// Unit conversions and variable definitions
const long double Tstar = HEOS.T()/HEOS.components[0]->transport.epsilon_over_k;
const long double sigma_nm = HEOS.components[0]->transport.sigma_eta*1e9; // 1e9 to convert from m to nm
const long double molar_mass_kgkmol = molar_mass*1000; // 1000 to convert from kg/mol to kg/kmol
/// Both the collision integral \f$\mathfrak{S}^*\f$ and effective cross section \f$\Omega^{(2,2)}\f$ have the same form,
/// in general we don't care which is used. The are related through \f$\Omega^{(2,2)} = (5/4)\mathfrak{S}^*\f$
@@ -113,7 +110,7 @@ long double TransportRoutines::modified_Batschinski_Hildebrand_viscosity_term(He
return S+F*delta*(1/(delta0-delta)-1/delta0); // Pa-s
}
else{
throw NotImplementedError("TransportRoutines::GeneralDiluteGasViscosity is only for pure and pseudo-pure");
throw NotImplementedError("TransportRoutines::modified_Batschinski_Hildebrand_viscosity_term is only for pure and pseudo-pure");
}
}
@@ -121,14 +118,9 @@ long double TransportRoutines::initial_density_dependence_viscosity_term(Helmhol
{
if (HEOS.is_pure_or_pseudopure)
{
//// HARD CODED FOR PROPANE FOR TESTING PURPOSES
double _b[]={-19.572881,219.73999,-1015.3226,2471.01251,-3375.1717,2491.6597,-787.26086,14.085455,-0.34664158};
std::vector<long double> b(_b,_b+sizeof(_b)/sizeof(_b[0]));
double _c[]={0,-0.25,-0.5,-0.75,-1.0,-1.25,-1.5,-2.5,-5.5};
std::vector<long double> c(_c,_c+sizeof(_c)/sizeof(_c[0]));
HEOS.components[0]->transport.epsilon_over_k = 263.88;
HEOS.components[0]->transport.sigma_eta = 0.49748e-9;
//// END HARD CODED
// Retrieve values from the state class
CoolProp::ViscosityRainWaterFriendData &data = HEOS.components[0]->transport.viscosity_initial.rainwater_friend;
const std::vector<long double> &b = data.b, &t = data.t;
long double B_eta, B_eta_star;
long double Tstar = HEOS.T()/HEOS.components[0]->transport.epsilon_over_k; // [no units]
@@ -136,14 +128,14 @@ long double TransportRoutines::initial_density_dependence_viscosity_term(Helmhol
long double summer = 0;
for (int i = 0; i < b.size(); ++i){
summer += b[i]*pow(Tstar, c[i]);
summer += b[i]*pow(Tstar, t[i]);
}
B_eta_star = summer; // [no units]
B_eta = 6.02214129e23*pow(sigma,3)*B_eta_star; // [m^3/mol]
B_eta = 6.02214129e23*pow(sigma, 3)*B_eta_star; // [m^3/mol]
return B_eta; // [m^3/mol]
}
else{
throw NotImplementedError("TransportRoutines::GeneralDiluteGasViscosity is only for pure and pseudo-pure");
throw NotImplementedError("TransportRoutines::initial_density_dependence_viscosity_term is only for pure and pseudo-pure");
}
}

2
src/Backends/Helmholtz/TransportRoutines.h
View File

@@ -63,7 +63,7 @@ public:
where \f$N_A\f$ is Avogadros number \f$6.022\times 10^{23}\f$ mol\f$^{-1}\f$ and \f$\sigma_{\eta}\f$ is in m.
\f[
B_{\eta}^*(T^*) = \displaystyle\sum_ib_i(T^*)^{c_i}
B_{\eta}^*(T^*) = \displaystyle\sum_ib_i(T^*)^{t_i}
\f]
IMPORTANT: This function returns \f$B_{\eta}\f$, not \f$\eta_{RF}\f$