ABSTRACT
Thermodynamics generally describes transformations between heat and mechanical work. When irreversible deformations are allowed, it is observed that volume fractions and component velocities are not thermodynamic variables. This is in stark contrast to the previous discussion of equilibrium thermodynamics, where they appeared to be thermodynamic variables. In hindsight, it is observed that they were proportional to the actual thermodynamic variables in the cases considered. Of particular importance to non-equilibrium thermodynamics are the modifications momentum flux, make to the Clapeyron equation and the new information about dispersion, porosity waves, fluid flow and their interactions obtained from the new Onsager's relations. The thermodynamic potentials were constructed in the case of two components and three components. These potentials are expressed in terms of the total momentum, the total mass, the momenta of interaction between the various phases and the mass fractions associated with these interactions.
