脉冲等离子体推力器羽流特性数值研究

以脉冲等离子体推力器羽流为研究对象,建立三维物理模型,简化并离散电子动量方程,运用单元粒子-直接模拟蒙特卡罗混合法模拟非稳态羽流流动.假定脉冲周期内推进剂粒子按正弦规律进入流场,分析流场中电势、电子、离子和原子数密度分布随着时间变化情况,并通过与已有实验数据的对比验证仿真模型.研究表明:模型能在垂直和平行于推力器极板的两个平面内预测等离子体羽流流场参数.该研究方法、结果对更深入研究脉冲等离子体推力器(PPT)羽流具有参考价值. 

Numerical study of plume characteristics of a pulsed plasma thruster

According to the plume of a pulsed plasma thruster, a three dimensional physical model in a Cartesian coordinate system was developed and the electron momentum equation was simplified to simulate the unsteady flow of plume employing particle-in-cell and direct simulation Monte-Carlo hybrid method. By assuming the number of propellant particles injected to the flow field followed a sinusoidal rule during a pulse period, the profiles of potential, electron, ion and neutral number density versus time were analyzed. Then the simulation model was verified by making comparisons between computational results and experimental data. The research indicated that the model could predict that parameters of the plasma plume in both parallel and perpendicular planes to electrodes. The efforts of this paper are referable for research and development of pulsed plasma thrusters.