Three species one-dimensional kinetic model for weakly ionized plasmas

TL;DR

This paper develops a one-dimensional kinetic model for weakly ionized plasmas with three species, incorporating realistic collision operators and solving the resulting equations with a stable numerical method, revealing significant effects of collisions on plasma dynamics.

Contribution

It introduces a novel three-species kinetic model with realistic collision terms and applies a stable numerical method to analyze plasma behavior under varying conditions.

Findings

Charge-neutral collisions significantly affect plasma dynamics.

Differences observed between constant and temperature-dependent collision frequencies.

The Propagator Integral Method effectively solves non-linear plasma equations.

Abstract

A three species one-dimensional kinetic model is presented for a spatially homogeneous weakly ionized plasma subjected to the action of a time varying electric field. Planar geometry is assumed, which means that the plasma dynamics evolves in the privileged direction of the field. The energy transmitted to the charges is be channelized to the neutrals thanks to collisions and impacting the plasma dynamics. Charge-charge interactions have been designed as a one dimensional collision term equivalent to the Landau operator used for fully ionized plasmas. Charge-neutral collisions are modelled by a conservative drift diffusion operator in the Doughertys form. The resulting set of coupled drift diffusion equations is solved with the stable and robust Propagator Integral Method. This method feasibility accounts for non-linear effects without appealing to linearisation or simplifications, providing conservative physically meaningful solutions. It is found that charge neutral collisions exert a significant effect since a quite different plasma dynamics arises if compared to the collisionless limit. In addition, substantial differences in the system evolution are found for constant and temperature dependent collision frequencies cases.