Anomalous electron transport in Hall-effect thrusters: Comparison between quasi-linear kinetic theory and particle-in-cell simulations
Anomalous electron transport in Hall-effect thrusters: Comparison between quasi-linear kinetic theory and particle-in-cell simulations
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霍尔效应推进器中的反常电子传输：准线性动力学理论与细胞内粒子模拟之间的比较
DOI：
10.1063/1.5017626
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发表时间：
2018
影响因子：
2.2
通讯作者：
A. Bourdon
中科院分区：
文献类型：
--
作者：
T. Lafleur;R. Martorelli;P. Chabert;A. Bourdon
动力学漂移不稳定性被认为是导致E × B放电（如霍尔效应推进器）中电子跨场输运异常的可能机制。这种不稳定性是由电子和离子漂移速度的巨大差异驱动的，这对建模工作提出了重大挑战，而无需采用耗时的粒子模拟（PIC）。在这里，我们测试方面的准线性动力学理论与2D PIC模拟的目的是开发一个自洽的治疗这些不稳定性。感兴趣的具体数量是不稳定性增长率（它决定了不稳定性幅度的空间和时间演变），和不稳定性增强的电子-离子摩擦力（这导致“异常”电子输运）。通过使用自洽获得的电子分布函数的PIC模拟（这是在一般非麦克斯韦），我们发现，准线性动力学理论的预测与模拟结果吻合得很好。相比之下，麦克斯韦分布的使用导致大约2-4倍高的生长速率和电子-离子摩擦力，并且因此显著地高估了电子传输。自洽建模的分布函数，而不需要PIC模拟的一种可能的方法进行了讨论。
Kinetic drift instabilities have been implicated as a possible mechanism leading to anomalous electron cross-field transport in E × B discharges, such as Hall-effect thrusters. Such instabilities, which are driven by the large disparity in electron and ion drift velocities, present a significant challenge to modelling efforts without resorting to time-consuming particle-in-cell (PIC) simulations. Here, we test aspects of quasi-linear kinetic theory with 2D PIC simulations with the aim of developing a self-consistent treatment of these instabilities. The specific quantities of interest are the instability growth rate (which determines the spatial and temporal evolution of the instability amplitude), and the instability-enhanced electron-ion friction force (which leads to “anomalous” electron transport). By using the self-consistently obtained electron distribution functions from the PIC simulations (which are in general non-Maxwellian), we find that the predictions of the quasi-linear kinetic theory are in good agreement with the simulation results. By contrast, the use of Maxwellian distributions leads to a growth rate and electron-ion friction force that is around 2–4 times higher, and consequently significantly overestimates the electron transport. A possible method for self-consistently modelling the distribution functions without requiring PIC simulations is discussed.
影响因子：
2.2
作者：
M. Turner;A. Derzsi;Z. Donkó;D. Eremin;S. Kelly;T. Lafleur;T. Mussenbrock
通讯作者：
M. Turner;A. Derzsi;Z. Donkó;D. Eremin;S. Kelly;T. Lafleur;T. Mussenbrock