离子发动机羽流二维轴对称数值模型与验证

Validation of two-dimensional axisymmetric plume model for ion thruster

为了解离子发动机羽流特别是交换电荷离子(CEX,Charge-Exchange)的分布和流动特性,建立了离子发动机羽流的物理模型,采用粒子网格(PCI,Particle in Cell)方法对2种型号的离子发动机羽流场进行数值模拟计算,与其地面实验数据进行对比分析.结果表明:在CEX离子密度大小及分布、电势的大小及最大电势梯度的位置、CEX离子流动角方面,模拟结果同实验结果符合得相当好.在电势结构方面,由于舱壁电势的影响,模拟结果同实验结果相比有一些差别.羽流模型和计算结果为相关羽流实验和数值模拟研究提供参考.

In order to understand the distribution and flow characteristic of ion plume especially the charge-exchange（CEX） ions,the ion thruster plume model was established and a numerical simulation using the particle-in-cell method was adopted to obtain CEX ions distribution in the plume.The calculation results were compared with the experimental results for the plume fields of two ion thrusters.It agrees well between calculation results and experimental results of CEX ions density distribution,magnitude of electrical potential,position of maximum electrical potential grads,CEX ion flow angle.Structures of electrical potential have somewhat differences because the experimental result is influenced by the vacuum tank wall.The ion thruster plume model and calculation results help for experimental and numerical simulation study of plume.