AN Alternative Two-Fluid Formulation Of a Partially Ionized Plasma

TL;DR

This paper introduces a new two-fluid model for partially ionized plasmas, combining ions and neutrals into one fluid and electrons as a separate fluid, to better understand wave modes in such systems.

Contribution

It proposes a novel two-fluid formulation called INe, where ions and neutrals are combined, differing from previous models that combined electrons and neutrals.

Findings

Analysis of characteristic wave modes in the INe-electron plasma.

Framework development for the INe fluid model.

Comparison with existing two-fluid plasma descriptions.

Abstract

In a recent paper (Krishan 2021), a two-fluid description of a partially ionized plasma was presented in which electron fluid and the neutral fluid were combined appropriately into one fluid, christened as ENe fluid, and treat the ions as the second fluid. Some of the electrostatic modes of this two-fluid system were studied. Here, I discuss another possibility in which the ion fluid and the neutral fluid are combined into one fluid, christened as INe fluid, and treat the electrons as the second fluid. There can be a huge variation between the relative masses of the neutrals and the ions. Thus both have to be treated as the inertia carrying species. After establishing the framework for the INe-electron fluids, some of the characteristic wave modes of this novel plasma are investigated.