Nonlinear transport processes and irreversible thermodynamics of a mixture of ionized and neutral gases subject to an electric field

Abstract

In this paper, the modified moment method is applied to investigate nonlinear transport processes and irreversible thermodynamics of a dilute mixture of nonpolarizable ionized and neutral gases subject to an external electric field. Theories are developed by means of scalar and tensor temperature distribution functions and the extended Gibbs relations are derived in both theories. The latter relations reduce to the equilibrium Gibbs relation as the fluxes vanish at equilibrium. Various nonlinear transport equations are obtained from which nonlinear transport coefficients can be derived. They all reduce to linear transport coefficients as the magnitudes of the fluxes get smaller. Especially, nonlinear diffusion and mobility coefficients are obtained which depend nonlinearly on the electric field strength, and their mutual relationships are found as generalizations of the Einstein relations.