This function is based on eq. 4 from [Slattery1958].
function pDstar_nonpolar
input Q.TemperatureAbsolute Tstar = 1 "Ratio of temperature to the geometric mean of the critical temperatures" annotation(
Dialog(__Dymola_label = "<html><i>T</i><sub>c AB</sub></html>"));
output Q.NumberAbsolute pDstar "Reduced pressure-diffusivity product";
end pDstar_nonpolar;