Return specific volumetric expansion coefficient as a function of pressure p, temperature T and composition X
function beta_pTX input Modelica.SIunits.AbsolutePressure p "Pressure"; input Modelica.SIunits.Temperature T "Temperature"; input Modelica.SIunits.MassFraction X[:] "Mass fractions "; output Real beta(unit = "1/K") "Volumetric expansion coefficient"; end beta_pTX;