The difference between the IG enthalpy and the actual gas enthalpy is given by the excess enthalpy which follows from the selected equation of state. In case you are using the ideal gas law the difference is zero, but this is not the case for any other EOS. So you can put your coefficients in, then pull gas enthalpy.Dtemperature out (e.g. plot vs temperature perhaps at several pressures, copy data out, copy to Excel), see how far you are off from the actual gas temperature derivative of enthalpy. This will tell you what ideal gas heat capacity (Cp = d h / d T at constant P) should be as a function of temperature and you can refit the coefficients using any of the formulas (which ever fits best).
Then for the liquid phase, if you are using an equation of state there are no more degrees of freedom as the EOS parameters are all determined from critical properties, which I presume are known. So if you have determined your IG heat capacity, your liquid enthalpy should be ok already, within the restrictions of the EOS you are using. If you are using an activity model however, there is the heat of vaporization that you will need to refit from the liquid enthalpy predicted and the liquid enthalpy you have. Refit any correlation, put it back in.
For solids, TEA only deals with compounds that cannot live in the solid phase, or can only live in the solid phase, at this point in time. The solid enthalpy model requires not IG heay capacity, but solid heat capacity. Best to fit that one immediately to the d h / d T data for the solid phase of course.Statistics: Posted by jasper — 26 March 2013, 15:13
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