Isentropic Incompressible Body

We have to distinguish between an isothermal incompressible body and an isentropic incompressible body. We characterize 

The fundamental equations for an incompressible body have been derived [1], In the following, we suppress the mol number as a variable. 

Since for the isentropic incompressible body we have the independent variables S and p as starting point, the enthalpy is a convenient thermodynamic function to handle this problem. We put 

Therefore, the volume must be a function of the entropy alone, V = V(S). This means also that the volume is only a function of the entropy alone and not a function of pressure  

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