Study On Structural Discharge And Optimization Of A Type Of Cylindrical Hall Thruster With A Magnetically Insulates Anode

With the rapid development of microsatellite technology,the urgent demand for the lightweight technology of space propulsion system has been triggered.Therefore,the research of low power aerospace engine is imminent.Hall thruster is an electrical propulsion device with simple structure,low quality,high specific impulse,and long life,which is to meet the small satellite space mission of choice.The low-power cylindrical Hall thruster(CHT)has the problems of low efficiency and serious surface sputtering in the design process.This paper is based on the low power CHT designed by the plasma advance laboratory of Harbin Institute of Technology.A series of optimization is used to study its discharge characteristics and improve the performance and life of the thruster.First,this paper presents a magnetically insulates anode structure which adjusts the distribution of the magnetic field in the discharge channel by adjusting the anode material and structure,and directs the characteristic magnetic f ield lines crossing the anode boundary to intersect the wall surface,so that the wall surface is high potential and excrete ions,which can improve the thruster performance and life.The influence of the structure of the magnetically insulates anode on the performance and life of the thruster was analyzed by the comparison experiment of the non-conducting anode structure thruster and the magnetically insulates anode structure thruster.In addition,the effect of the magnetically insulates anode structure on the ionization acceleration characteristics of the thruster was analyzed by PIC simulation method,and the influence of the magnetically insulates anode on the performance and life of the thruster was explained by the simulation method.After that,we study the matching relationship between the low power CHT characteristic intersection and the ceramic channel of the magnetic structure of the magnetic structure by means of simulation.The radial dimension of the anode was changed by FEMM two-dimensional magnetic field simulation method,and the intersection of the characteristic magnetic field lines and the ceramic channel crossing the anode boundary was separated from the bottom of the ceramic channel.The position of the intersection of the ceramic channel was analyzed by PIC simulation to analyze ionization acceleration process and wall energy deposition process.Secondly,this paper analyzes the influence of channel diameter and channel length on the CHT performance of magnetically insulates anode,and uses the design method of variable cross-section channel to analyze the influence of variable crosssection channel design on the performance of the thruster.The optimal channel size of the thruster is studied by the above experimental results.Finally,we propose a vortex outlet mode,by changing the thrust angle of the anode outlet of the thruster,so that the working gas in the discharge channel to form a circumferential vortex diffusion.The influence of the vortex outlet mode on the density distribution of the neutral gas in the discharge channel of the thruster was studied by COMSOL finite element analysis software.The vortex venting method was used to study the effect of the vortex blower Performance impact.In addition,this chapter carries out the comprehensive performance test experiment,combined with the magnetically insulates anode,the variable cross section design scheme,the vortex blowout design scheme and so on to optimize the thruster,and analyze the influence of the comprehensive performance optimization scheme on the original low power CHT performance and life.