Diagnostic and modelling investigation on the ion acceleration and plasma throttling effects in a dualemitter hollow cathode micro-thruster  

作　　者：Zhongxi NING Chenguang LIU Ximing ZHU Yanfei WANG Bingjian AN Daren YU 

机构地区：[1]Plasma Propulsion Laboratory,Harbin Institute of Technology,Harbin 150001,China

出　　处：《Chinese Journal of Aeronautics》2021年第12期85-98,共14页中国航空学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.61571166,11775063 and 51736003)。

摘　　要：Hollow cathode discharges are widely used as neutralizers for the electric propulsion systems and recently developed into micro-thrusters for the small satellites.In this work,a dualemitter hollow cathode thruster is developed,which can be operated in two different modes—the neutralizer mode and the micro-thruster mode.For characterizing this kind of new device,the Langmuir probe,Faraday probe,and retarding potential analyzer are used to determine the electron temperature,electron density,ion flux,and ion energy distribution function.The operating parameters,including the thrust,and specific impulse,are also measured.A two-dimensional self-consistent extended fluid model is employed to calculate the spatial distribution of plasma parameters and the fluid field of electrons in the region around the emitters.By comparing the diagnostic and modelling results,it is found that the change in the electric field and ionization zone is the essential reason for the different performances of the device in the neutralizer and micro-thruster modes.Variation in the electric field leads to an ion acceleration effect in the micro-thruster mode;moving of the ionization zone raises the plasma pressure in the orifice region of the hollow cathode,and thus leads to enhanced plasma throttling and gas expanding effects.By analyzing the above mechanisms,the possible methods for improving this kind of hollow cathode micro-thruster are discussed.

关 键 词：Extended fluid model Hollow cathodes MICRO-THRUSTER Plasma contactor Plasma throttling effect 

分 类 号：V439.2[航空宇航科学与技术—航空宇航推进理论与工程]