This function computes the specific enthalpy of the fluid, but neglects the (small) influence of the pressure term p/d.
function specificEnthalpy_pTX extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input Temperature T "Temperature"; input MassFraction X[nX] "Mass fractions"; output SpecificEnthalpy h "Specific enthalpy"; end specificEnthalpy_pTX;