This information is part of the Modelica Standard Library maintained by the Modelica Association.

A minor approximation is used: the reference density is used instead of the real one, which would require a numeric solution.

h_is = isentropicEnthalpy(p_downstream, refState)

p_downstream	Type: AbsolutePressure (Pa) Description: Downstream pressure
refState	Type: ThermodynamicState Description: Reference state for entropy

h_is	Type: SpecificEnthalpy (J/kg) Description: Isentropic enthalpy