采用粒子网格单元和蒙特卡罗碰撞方法,建立了离子推力器羽流场的2维轴对称模型,对其特性进行了数值模拟,并将模拟结果与实验测量数据进行了对比分析。研究结果表明:数值模拟结果与实验测量值基本一致,模型可以很好地评估离子推力器的羽流特性;返流区离子数密度达到1014 m-3量级,会对航天器表面产生污染;背压对束流区域外电荷交换离子影响较为显著,不可忽略。

With particle-in-cell and Monte Carlo collision method,a two dimensional axisymmetric model is established to study the ion thruster plume characteristics. The simulated results are compared with experimental data,which shows good agreement and suggests that,the model can evaluate the characteristics of ion thruster plume very well. The ion number density can reach 1014 m-3 in the backflow region,which can cause erosion of the spacecraft;the back pressure’s visible influence on the charge exchange ions outside the beam region can not be neglected.