离子推力器羽流特性及其污染分析

介绍了与电推进系统有关的空间环境效应的形成原因及其对航天器性能、寿命等的影响。阐述了离子火箭发动机羽流内束离子、中性推进剂原子、交换电荷（CEX）离子和电子等主要成分与航天器相互作用的过程及机理。分析表明，离子推力器出口处的中性推进剂原子与高速束离子流碰撞后产生的CEX离子Xe^＋，以及带电离子轰击推力器组件特别是加速极所产生的金属CEX离子，是造成离子火箭发动机羽流污染的主要成分。在此基础上提出了若干防污染措施。

Analysis on Plume Contamination and Its Characteristic of Ion Thruster

The reason of space environment effect related to electric thruster system and its affection to performance and lifetime of spacecraft were introduced in this paper. The interaction process and mechanism between the spacecraft and major component in plume of ion thruster, such as beam ion, neutral propellant atom, change electronic (CEX) ion and electron were also presented. The analysis results showed that the Xe+ of CEX produced in the collision of neutral propellant atom with high speed cluster ion flow at thruster outlet, and metal ion of CEX produced by electric ion bombarding thruster assembly were the main component to cause plume contamination of ion thruster. At last, some measurements were put forward to prevent spacecraft from contamination.