Simulation of dust grain charging under hypervelocity impact plasma environment

Xiao Jun Zhou, Xiao Wei Chen*

*此作品的通讯作者

科研成果: 期刊稿件文章同行评审

摘要

Dust plasma readily forms during hypervelocity impact, which serves as a source of plasma macroscopic charge separation and strong electromagnetic fields. In this study, we examine the dynamic evolution of surface charging of aluminum dust grains with micrometer or submicrometer sizes in a hypervelocity impact plasma environment based on the theory of orbital motion limited. As dust grains traverse the expanding plasma, plasma density and temperature decrease with increasing distance from the impact point. This leads to longer relaxation times for charging equilibrium (ranging from picoseconds to microseconds) and reduced equilibrium charges. The model incorporates thermionic and secondary electron emission effects on dust grain charging processes while also examining the impacts of five heating and cooling mechanisms on the thermal equilibrium temperatures of dust grains. Near the impact point, thermal equilibrium temperatures exceed aluminum's boiling point, which results in phase transition ablation processes. As dust grain temperatures increase, thermionic emission currents may dominate charging dynamics and influence final equilibrium charge numbers. High-temperature dust grains tend to acquire positive charges. Moreover, we observe that the radius of dust grains considerably affects charging processes, and smaller grain radii correspond to low equilibrium charges and longer relaxation times.

源语言英语
文章编号023703
期刊Physics of Plasmas
31
2
DOI
出版状态已出版 - 1 2月 2024

指纹

探究 'Simulation of dust grain charging under hypervelocity impact plasma environment' 的科研主题。它们共同构成独一无二的指纹。

引用此

Zhou, X. J., & Chen, X. W. (2024). Simulation of dust grain charging under hypervelocity impact plasma environment. Physics of Plasmas, 31(2), 文章 023703. https://doi.org/10.1063/5.0183745