This function calculates the time derivative of vapor density of R134a with regard to the time derivative of p. The non-derivative function is dewDensity.
It is only valid in the two-phase region (i.e., ptriple ≤ p ≤ pcrit ).
function dDewDensity_dPressure_der_sat extends Modelica.Icons.Function; input SaturationProperties sat "Saturation properties | pressure is used for interpolation"; input SaturationProperties der_sat "Derivative of saturation properties"; output Real der_ddvdp "Time derivative of vapor density in two-phase region w.r.t. pressure"; end dDewDensity_dPressure_der_sat;