Generalized enthalpy based equation of state for multi-component mixtures

Abstract

An equation of state using pressure and temperature as independent variables, including non-equilibrium thermal energies of components and explicit accounting of thermal electron effects, is formulated for multi component mixtures. As pressure equilibration is faster in mixtures, this approach is more suited than earlier schemes using Mie-Gruneisen equation of state. Due to the reliance on enthalpy, in lieu of energy, it is directly applicable also to treat porosity effects. The formulation leads to an expression for mixture volume which consists of a term depended on enthalpy differences of components, in addition to those depending on average mixture parameters. A method to estimate non-equilibrium thermal effects, using component Hugoniot to compute non-equilibrium temperatures, is also proposed in this work. Results obtained for two and three component mixtures compare well with experimental Hugoniot data.