static IF97REGIONS RegionDetermination_pX(double p, double X, IF97Parameters inkey)
{
// Setup needed Region Equations for region determination
// Saturation Region Limit Variables
double Tsat = 0;
double Xliq = 0;
double Xvap = 0;
// Check overall boundary limits
if ((p < Constants.Pmin) || (p > Constants.Pmax))
throw new ArgumentOutOfRangeException("Pressure out of range");
double Xmin = R1.output(inkey, Constants.Tmin, p);
double Xmax = R2.output(inkey, Constants.Tmax, p);
if ((X < Xmin) || (X > (Xmax + 1.0E-10)))
{
if (inkey == IF97Parameters.h)
{
throw new ArgumentOutOfRangeException("Enthalpy out of range");
}
else
{
throw new ArgumentOutOfRangeException("Entropy out of range");
}
}
// Check saturation Dome first
if (p <= Constants.Pcrit)
{
Tsat = Region4.Tsat97(p);
Xliq = R1.output(inkey, Tsat, p);
Xvap = R2.output(inkey, Tsat, p);
if ((Xliq <= X) && (X <= Xvap))
{ // Within Saturation Dome
return IF97REGIONS.REGION_4; // Region 4
}
}
// End Check saturation Dome
// Check values below 16.529 MPa
if (p <= Constants.P23min)
{ // p <= P23min (saturation dome)
if (X <= Xliq) return IF97REGIONS.REGION_1;
else if (X >= Xvap) return IF97REGIONS.REGION_2;
else return IF97REGIONS.REGION_4;
}
// Check values above 16.529 MPa
else if (X <= R1.output(inkey, Constants.T23min, p))
return IF97REGIONS.REGION_1;
else if (X >= R2.output(inkey, Region23_p(p), p))
return IF97REGIONS.REGION_2;
else
return IF97REGIONS.REGION_3;
} // Region Output backward
static IF97REGIONS RegionDetermination_TP(double T, double p)
{
if (T > Constants.Text)
{
throw new ArgumentOutOfRangeException("Temperature out of range");
}
else if (T > Constants.Tmax && T <= Constants.Text)
{
if (p <= Constants.Pext)
{
return IF97REGIONS.REGION_5;
}
else
{
throw new ArgumentOutOfRangeException("Pressure out of range");
}
}
else if (T > Constants.T23min && T <= Constants.Tmax)
{
if (p > Constants.Pmax)
{
throw new ArgumentOutOfRangeException("Pressure out of range");
}
else if (p < 16.5292)
{ // Check this one first to avoid the call to 2-3 boundary curve (a little bit faster)
return IF97REGIONS.REGION_2;
}
else if (p > Region23_T(T))
{
return IF97REGIONS.REGION_3;
}
else
{
return IF97REGIONS.REGION_2;
}
}
else if (T >= Constants.Tmin && T <= Constants.T23min)
{
if (p > Constants.Pmax)
throw new ArgumentOutOfRangeException("Pressure out of range");
else if (p > Region4.p_T(T))
return IF97REGIONS.REGION_1;
else if (p < Region4.p_T(T))
return IF97REGIONS.REGION_2;
else
return IF97REGIONS.REGION_4;
}
else
{
throw new ArgumentOutOfRangeException("Temperature out of range");
}
}
/// Get surface tension [N/m] as a function of T [K]
public static double sigma97(double T)
{
return Region4.sigma_t(T);
}
/// Get the saturation pressure [Pa] as a function of T [K]
public static double psat97(double T)
{
return Region4.p_T(T);
}
// ******************************************************************************** //
// 2-Phase Functions //
// ******************************************************************************** //
/// Get the saturation temperature [K] as a function of p [Pa]
public static double Tsat97(double p)
{
return Region4.T_p(p);
}
