霍尔推力器放电通道溅射腐蚀计算

摘要

为了预示霍尔推力器的寿命,建立了推力器粒子束放电通道的2维电磁场模型,模拟的推进剂为氙.利用PIC方法跟踪粒子在电磁场中的运动.磁场的求解采用拉普拉斯方程,电场的求解采用泊松方程.电子由阴极喷入通道,并在电磁场中与原子发生电离碰撞生成离子.在跟踪离子的过程中记录下撞击到内外壁面的离子个数、角度和能量.利用记录下的参数进行腐蚀计算,得到当溅射阈值能量分别为10,20,30,40,50 eV时通道壁面的腐蚀速率.推力器放电通道出口附近的最大腐蚀速率约为1.7×10-9m/s.%To calculate the lifetime of a Hall thruster, a two-dimensional model of magnetic and electric fields was established for the discharge channel of the thruster, and the assumed propellant is the xenon. The movement of particles in the magnetic and electric fields was tracked using PIC method. The Laplace equation was used to calculate the magnetic field , and the Poisson equation to calculate the electric field. Electrons were injected from the cathode and then ions were generated from the atom-electron ionization collision. In the process of tracking, we recorded the number, angle and energy of ions hitting against the inner and outer walls. Then we calculated the erosion rate at the threshold energy of 10, 20, 30, 40 and 50 eV, respectively. The maximal erosion rate at the outlet is 1. 7X 10-9 m/s.