MODE = PS (=26)

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MODE = PS (26)

Note: If the $ConvertEESREFPROPUnits directive is used in the EES program, inputs should be provided in the unit system defined in EES and outputs will be automatically converted to the unit system defined in EES. The units shown for inputs and outputs in the following description apply when the $CONVERTEESREFPROPUNITS directive is not used.

Description: Calculate thermodynamic properties for given pressure and specific entropy
     In1 = Pressure in kPa
     In2 = Specific entropy in kJ/K-kmol
     In3 = mole fraction of first component (skip for pure fluid)
     ...
     InN = mole fraction of next to last component
            Note: If the /mass flag is provided with the $CONVERTEESREFPROPUNITS directive, mass fractions should be provided instead of mole fractions.

     Out1 = Temperature in K
     Out2 = Pressure in kPa
     Out3 = Density in kmol/m3
     Out4 = Specific volume in m3/kmol
     Out5 = Specific enthalpy in kJ/kmol
     Out6 = Specific entropy in kJ/K-kmol
     Out7 = Quality (<0 for subcooled liquid, >1 for superheated vapor)
     Out8= Specific heat at constant volume (Cv) in kJ/K-kmol
     Out9 = Specific heat at constant pressure (Cp) in kJ/K-kmol
     Out10 = Speed of sound in m/sec (not applicable for two-phase state)
     Out11 = Quality (mass basis) (<0 for subcooled liquid, >1 for superheated vapor)
     Out12..12+N = mole fractions of the liquid phase for the N components in the mixture
               Note: Mass fractions (in place of mole fractions) are output if the /mass flag is provided with the $CONVERTEESREFPROPUNITS directive
      Out12+N+1..Out12+2N = mole fractions of the vapor phase for the N components in the mixture
               Note: Mass fractions (in place of mole fractions) are output if the /mass flag is provided with the $CONVERTEESREFPROPUNITS directive

Example 1:
PS=26              "mode for flash calculation, given pressure and specific entropy"
mf=0.3               "mole fraction"
Call ees_refprop('R32+R134a', PS, 1000 [kPa], 30.0 [kJ/kmol-K], mf : T,P,rho,v,h,s,Q,Cv,Cp,w,Qm,x_R32,x_R134a,y_R32,y_R134a)

{Solution:
Cp=109.3 [kJ/kmol-K]
Cv=72.78 [kJ/kmol-K]
h=4365 [kJ/kmol]
mf=0.3
P=1000 [kPa]
PS=26
Q=-1.314
Qm=-1.314
rho=18.1 [kmol/m^3]
s=30 [kJ/K-kmol]
T=157.3 [K]
v=0.05524 [m^3/kmol]
w=1211 [m/s]
x_R134a=0.7
x_R32=0.3
y_R134a=0.7
y_R32=0.3
}

Example 2:
$UnitSystem SI C kPa mass
$ConvertEESREFPROPUnits /mass
PS=26                "mode for flash calculation, given density and specific entropy"
Fluid$='R134a'
P_in=100 [kPa]
s_in=1 [kJ/kg-K]
$varInfo T units=C
$varInfo P units=kPa
$varInfo rho units=kg/m^3
$varinfo v units=m^3/kg
$varinfo h units=kJ/kg
$varinfo s units=kJ/kg-K
Call ees_refprop(Fluid$, PS, P_in, s_in : T, P, rho, v , h, s, Q)

{Solution:
Fluid$='R134a'
h=198.1 [kJ/kg]
P=100 [kPa]
PS=26
P_in=100 [kPa]
Q=0.1505
rho=33.79 [kg/m^3]
s=1 [kJ/kg-K]
s_in=1 [kJ/kg-K]
T=-26.36 [C]
v=0.0296 [m^3/kg]
}

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