Evolution of the Radiative Thermal Instability in a Confined Medium

TL;DR

This paper investigates how the evolution of thermally bistable clouds changes when pressure is treated as a dynamic variable, revealing new behaviors and instabilities relevant to laboratory and fusion plasmas.

Contribution

It introduces a self-consistent model for cloud evolution with variable pressure, uncovering new stable states and secondary instabilities not seen in isobaric analyses.

Findings

Derived solutions for cloud evolution with pressure dynamics

Identified additional stable configurations of clouds

Discovered secondary instabilities relevant to plasma applications

Abstract

Thermally bistable fluid tends to self-organize into clouds of hot and cold material, which are internally uniform and separated by thin conduction fronts. The evolution of these clouds has been studied for isobaric systems, but when pressure is instead treated as a dynamical quantity and allowed to evolve self-consistently, fundamentally different dynamics appear. Such a treatment is necessary in some laboratory plasmas, whose volume is constrained but whose pressure can vary. Solutions are derived for the evolution of clouds, accounting for pressure variation and interactions between conduction fronts. Additional stable configurations and secondary instabilities are derived, which may be relevant to fusion plasmas and to the study of photoionized plasma in the laboratory.