specific heat calculation
 

Hi guys.

I hope someone can help me out here as I am very confused as to how FLUENT is calculating my pressure inlet values.

According to the user manual, Mach number is found from P and P_total using isentropic relations.
Then, T is found from T_total and Mach using isentropic relations.

Where does specific heat ratio come into here?
It is needed to find Mach number from pressure, but how do they estimate specific heat if Temperature is not known yet?

I am so confused. Please help!
Panboy