some questions about the udf for specificed heat in the FLUENT 14.5 V
 

hello everyone ,
recently, i do a research related to the supercrirtical CO2. therefore, i need to use the UDF to define the thermal physical properties such as Cp, density and so on.
here , i don't understand the function of the macro:DEFINE_SPECIFIC_HEAT.
what i know is that it can identify the capable heat when the CP is the function of temperature. according the Ansys14.5 help document, it wirites the code for the sensible enthalpy like :*h=cp*(T-Tref). my question is :does the enthalpy equation affect the result ？ the formula for the enthalpy mentioned at the Ansys14.5 help document is the only equaton ?
any answers will be appreiate .:)