Kinetic theory of two-temperature polyatomic plasmas

TL;DR

This paper develops a kinetic theory framework for non-thermal, two-temperature polyatomic plasmas, deriving fluid equations and transport coefficients that account for electron-heavy species non-equilibrium.

Contribution

It introduces a novel kinetic model for reactive polyatomic plasmas with separate electron and heavy-species temperatures, including new transport flux expressions.

Findings

Derived zeroth and first-order fluid equations.

Expressed transport coefficients as bracket products.

Provided a consistent fluid model for non-thermal plasmas.

Abstract

We investigate the kinetic theory of two-temperature plasmas for reactive polyatomic gas mixtures. The Knudsen number is taken proportional to the square root of the mass ratio between electrons and heavy-species, and thermal non-equilibrium between electrons and heavy species is allowed. The kinetic non-equilibrium framework also requires a weak coupling between electrons and internal energy modes of heavy species. The zeroth-order and first-order fluid equations are derived by using a generalized Chapman-Enskog method. Expressions for transport fluxes are obtained in terms of macroscopic variable gradients and the corresponding transport coefficients are expressed as bracket products of species perturbed distribution functions. The theory derived in this paper provides a consistent fluid model for non-thermal multicomponent plasmas.