Compressing turbulence and sudden viscous dissipation with compression-dependent ionization state

TL;DR

This paper investigates how the ionization state of plasma influences turbulence dissipation during rapid compression, revealing that increased ionization can prevent sudden viscous dissipation and alter turbulent energy evolution.

Contribution

It demonstrates that plasma ionization during compression can prevent sudden viscous dissipation and significantly impact turbulence behavior, a novel insight into plasma compression dynamics.

Findings

Ionization increases can prevent sudden viscous dissipation.

Ionization leads to larger turbulent energy increases.

Net viscosity dependence on compression is regime-specific.

Abstract

Turbulent plasma flow, amplified by rapid 3D compression, can be suddenly dissipated under continuing compression. This effect relies on the sensitivity of the plasma viscosity to the temperature, $\mu \sim T^{5/2}$. The plasma viscosity is also sensitive to the plasma ionization state. We show that the sudden dissipation phenomenon may be prevented when the plasma ionization state increases during compression, and demonstrate the regime of net viscosity dependence on compression where sudden dissipation is guaranteed. Additionally, it is shown that, compared to cases with no ionization, ionization during compression is associated with larger increases in turbulent energy, and can make the difference between growing and decreasing turbulent energy.