// HFC134a

#include "HFC134a.h"
#include <math.h>

const double 
    M = 102.032,
    Tmn = 170.0,
    Tmx = 455.0,
    Tc = 374.18,
    Pc = 4056290.0,
    Roc = 508.0,
    R = 81.48885644;

const double a134[] = {
	0.5586817e-1,
	0.4982230,
	0.2458698e-1,
	0.8570145e-3,
	0.4788584e-3,
	-0.1800808e1,
	0.2671641,
	-0.4781652e-1,
	0.1423987e-1,
	0.3324062,
	-0.7485907e-2,
	0.1017263e-3,
	-0.5184567,
	-0.8692288e-1,
	0.2057144,
	-0.5000457e-2,
	0.4603262e-3,
	-0.3497836e-2,
	0.6995038e-2,
	-0.1452184e-1,
	-0.1285458e-3
};

const double t134[] = {
	-0.5, 0.0, 0.0, 0.0, 1.5, 1.5, 2.0, 2.0, 1.0, 3.0, 5.0,
	 1.0, 5.0, 5.0, 6.0, 10.0, 10.0, 10.0, 18.0, 22.0, 50.0
};

const int d134[] = {
	2, 1, 3, 6, 6, 1, 1, 2, 5, 2, 2,
	4, 1, 4, 1, 2, 4, 1, 5, 3, 10
};

const double b134[] = {
	-1.019535,
	 9.047135,
	-1.629789,
	-9.723916,
	-3.927170
};

double HFC134a::fp() {
	double sum1 = 0.0, sum2 = 0.0, sum3 = 0.0, 
		   sum4 = 0.0, sum5 = 0.0;
	double tau = Tc/T;
	double delta = Rho/Roc;

	double phi0 = b134[0] + b134[1]*tau + b134[2]*log(tau)
		          + log(delta) + b134[3]/sqrt(tau) + b134[4]*pow(tau,-0.75);
	int i;
	for (i = 0; i<8; i++)
		sum1 += a134[i]*pow(tau,t134[i])*pow(delta,d134[i]);
    for (i = 8; i<11; i++)
		sum2 += a134[i]*pow(tau,t134[i])*pow(delta,d134[i]);
	for (i = 11; i<17; i++)
		sum3 += a134[i]*pow(tau,t134[i])*pow(delta,d134[i]);
	for (i = 17; i<20; i++)
		sum4 += a134[i]*pow(tau,t134[i])*pow(delta,d134[i]);
	sum5 = a134[20]*pow(tau,t134[20])*pow(delta,d134[20]);
    double phir = sum1 + exp(-delta)*sum2 + exp(-delta*delta)*sum3
		          + exp(-delta*delta*delta)*sum4
				  + exp(-delta*delta*delta*delta)*sum5;
	return R*T*(phir + phi0);
}

double HFC134a::up() {
	double sum1 = 0.0, sum2 = 0.0, sum3 = 0.0, 
		   sum4 = 0.0, sum5 = 0.0;
	double tau = Tc/T;
	double delta = Rho/Roc;

	double phi0t = b134[1]*tau + b134[2]
		          - 0.5*b134[3]*pow(tau,-0.5) - 0.75*b134[4]*pow(tau,-0.75);
	int i;
	for (i = 0; i<8; i++)
		sum1 += a134[i]*t134[i]*pow(tau,t134[i])*pow(delta,d134[i]);
    for (i = 8; i<11; i++)
		sum2 += a134[i]*t134[i]*pow(tau,t134[i])*pow(delta,d134[i]);
	for (i = 11; i<17; i++)
		sum3 += a134[i]*t134[i]*pow(tau,t134[i])*pow(delta,d134[i]);
	for (i = 17; i<20; i++)
		sum4 += a134[i]*t134[i]*pow(tau,t134[i])*pow(delta,d134[i]);
	sum5 = a134[20]*t134[20]*pow(tau,t134[20])*pow(delta,d134[20]);
    double phirt = sum1 + exp(-delta)*sum2 + exp(-delta*delta)*sum3
		          + exp(-delta*delta*delta)*sum4
				  + exp(-delta*delta*delta*delta)*sum5;
	return R*T*(phirt + phi0t);
   }

double HFC134a::Pp(){
	double sum1 = 0.0, sum2 = 0.0, sum3 = 0.0, 
		   sum4 = 0.0, sum5 = 0.0;
	double tau = Tc/T;
	double delta = Rho/Roc;

	double phi0d = 1.0/delta;

	int i;
	for (i = 0; i<8; i++)
		sum1 += a134[i]*pow(tau,t134[i])*d134[i]*pow(delta,d134[i]-1);
    for (i = 8; i<11; i++)
		sum2 += a134[i]*pow(tau,t134[i])*(d134[i] - delta)*pow(delta,d134[i]-1);
	sum2 *= exp(-delta);
	double dk = delta*delta;
	for (i = 11; i<17; i++)
		sum3 += a134[i]*pow(tau,t134[i])*(d134[i] - 2.0*dk)*pow(delta,d134[i]-1);
	sum3 *= exp(-dk);
	dk *= delta;
	for (i = 17; i<20; i++)
		sum4 += a134[i]*pow(tau,t134[i])*(d134[i] - 3.0*dk)*pow(delta,d134[i]-1);
	sum4 *= exp(-dk);
	dk *= delta;
	sum5 = a134[20]*pow(tau,t134[20])*(d134[20] - 4.0*dk)*pow(delta,d134[20]-1);
    sum5 *= exp(-dk);
    double phird = sum1 + sum2 + sum3 + sum4 + sum5;
	return R*T*delta*delta*Roc*(phird + phi0d);
   }


double HFC134a::Psat(){
   if ((T < Tmn) || (T > Tc)) set_Err(TempError);
   double x1 = T/Tc;
   double x2 = 1.0 - x1;
   double f = -7.686556*x2 + 2.311791*pow(x2,1.5)
	          - 2.039554*x2*x2 - 3.583758*pow(x2,4);
   return Pc*exp(f/x1);
   }

/*
double HFC134a::dPsatdT(){
   if ((T < Tmn) || (T > Tc)) set_Err(TempError);
   double x1 = T/Tc;
   double x2 = 1.0 - x1;
   double f = -7.686556*x2 + 2.311791*pow(x2,1.5)
	          - 2.039554*x2*x2 - 3.583758*pow(x2,4);
   double fp = -7.686556 + 1.5*2.311791*pow(x2,0.5)
	          - 2.0*2.039554*x2 - 4.0*3.583758*pow(x2,3);
   return -Pc*exp(f/x1)*(fp/T + f/(x1*T));
   }
*/

double HFC134a::ldens(){
   if ((T < Tmn) || (T > Tc)) set_Err(TempError);
   double x1 = T/Tc;
   double x2 = 1.0 - x1;
   return 518.2 + 884.13*pow(x2,1.0/3.0) + 485.84*pow(x2,2.0/3.0)
	      + 193.29*pow(x2,10.0/3.0);
}

 double HFC134a::Tcrit() {return 374.21;}
 double HFC134a::Pcrit() {return 4059280.0;}
 double HFC134a::Vcrit() {return 1.0/511.95;}
 double HFC134a::Tmin() {return Tmn;}
 double HFC134a::Tmax() {return Tmx;}
 char * HFC134a::name() {return "HFC-134a";}
 char * HFC134a::formula() {return "C2F4H2";}
 double HFC134a::MolWt() {return M;}