The erosion loss of cathode is essential for the lifetime of magnetoplasmadynamic thruster(MPDT).In this work,an endurance test system for MPDT cathodes was designed and developed,and the erosion characteristics,erosi...The erosion loss of cathode is essential for the lifetime of magnetoplasmadynamic thruster(MPDT).In this work,an endurance test system for MPDT cathodes was designed and developed,and the erosion characteristics,erosion rate and erosion mechanism of the cathode were studied using the system under vacuum condition.The WCe20 hollow cathode was selected to carry out the long-term erosion of 540 h with the argon propellant supply flow rate of40 ml min^(-1),the input current of 25 A,and the central magnetic field intensity of 96 Gs.In order to predict the theoretical service life of cathode,a steady state erosion numerical model was established.The calculation results show that the total erosion rate of sputtering and evaporation is 11.58 mg h^(-1),which is slightly smaller than the test data of the average cathode corrosion rate of 12.70 mg h^(-1) in the experiment,because the experimental value includes start-up erosion rate.展开更多
This paper presents a method to measure the in situ magnetic field in a Hall thruster by optical non-invasive means, based on the optical Faraday rotation effect.This method does not affect the discharge of the thrust...This paper presents a method to measure the in situ magnetic field in a Hall thruster by optical non-invasive means, based on the optical Faraday rotation effect.This method does not affect the discharge of the thruster.Furthermore, its time resolution depends on the speed of the photodetector, and measurement at a MHz scale can be achieved.展开更多
文摘The erosion loss of cathode is essential for the lifetime of magnetoplasmadynamic thruster(MPDT).In this work,an endurance test system for MPDT cathodes was designed and developed,and the erosion characteristics,erosion rate and erosion mechanism of the cathode were studied using the system under vacuum condition.The WCe20 hollow cathode was selected to carry out the long-term erosion of 540 h with the argon propellant supply flow rate of40 ml min^(-1),the input current of 25 A,and the central magnetic field intensity of 96 Gs.In order to predict the theoretical service life of cathode,a steady state erosion numerical model was established.The calculation results show that the total erosion rate of sputtering and evaporation is 11.58 mg h^(-1),which is slightly smaller than the test data of the average cathode corrosion rate of 12.70 mg h^(-1) in the experiment,because the experimental value includes start-up erosion rate.
基金the support of National Natural Science Foundation of China (No.51807006)
文摘This paper presents a method to measure the in situ magnetic field in a Hall thruster by optical non-invasive means, based on the optical Faraday rotation effect.This method does not affect the discharge of the thruster.Furthermore, its time resolution depends on the speed of the photodetector, and measurement at a MHz scale can be achieved.