摘要
针对现有离子推力器栅极系统束流引出分析中未考虑放电室等离子体密度均匀性影响的不足,基于数值方法对该问题进行了研究。采用单元内粒子(Particle In Cell,PIC)方法对栅极系统束流引出进行了数值模拟。PIC方法中电场求解采用有限差分方法,离子加速方法采用跳蛙格式。以国产20cm Xe离子推力器作为算例,计算得到了栅极中心和边缘孔引出束流离子和电场的分布。结果显示栅极中心孔相对边缘孔束流聚焦性好,束流发散角小,但中心孔轴线的鞍点电势较边缘孔高24.8V。因此,放电室等离子体密度分布对束流引出具有重要影响,电子返流现象最先出现在栅极中心位置。
Present analyses on the ion beam of the grid system do not take account the plasma density in discharger chamber. Ion beam extraction was simulated by the particle in cell （PIC） method. The electric field was calculated by the finite differential method （FDM）, and the ion particles were accelerated by the leap-frog method. With Chinese 20-centimeter Xe ion thruster, the electric potential and ion beam distributions in the center and brim aperture of grid system were obtained. The results show that the ion beam extracted by the center aperture has better focus property and smaller divergence angle than that of the brim ion beam. However, the saddle point potential of the center aperture is 24. 8V, higher than that of the brim. Hence, the plasma density in discharger chamber has an important effect on the ion beam extraction, and electron back-streaming phenomena take place on the center position of grid system firstly.
出处
《中国空间科学技术》
EI
CSCD
北大核心
2012年第3期72-77,共6页
Chinese Space Science and Technology
基金
真空低温技术与物理重点试验室基金(9140C550211120C5501
9140C5504050902)资助项目
作者简介
贾艳辉,1983年生，2009年获兰州大学粒子与原子核物理专业硕士学位，现为兰州空间技术物理研究所物理电子学专业博士研究生。研究方向为放电等离子电推力器技术与工程。
