Effects of magnetic field strength in the discharge channel on the performance of a multi-cusped field thruster

Peng Hu,Daren Yu,Yuanyuan Gao,Hui Liu

doi:10.1063/1.4962548

Abstract

The performance characteristics of a Multi-cusped Field Thruster depending on the magnetic field strength in the discharge channel were investigated. Four thrusters with different outer diameters of the magnet rings were designed to change the magnetic field strength in the discharge channel. It is found that increasing the magnetic field strength could restrain the radial cross-field electron current and decrease the radial width of main ionization region, which gives rise to the reduction of propellant utilization and thruster performance. The test results in different anode voltage conditions indicate that both the thrust and anode efficiency are higher for the weaker magnetic field in the discharge channel.

Highlights

The Multi-cusped Field Thruster is a novel concept in electric propulsion, and it was investigated as early as 1962 by Janes et al.[1]
All the results demonstrated that the ionization process in the discharge channel is closely related with the cusped field there, and this naturally raises the question of how the strength of magnetic field in the discharge channel affect the ionization aElectronic mail: yudaren@hit.edu.cn 2158-3226/2016/6(9)/095003/8
It is found that increasing the magnetic field strength in the discharge channel could lead to the decrease of radial cross-field electron current, and a narrower ionization region can be formed, as a result, the atoms near the wall cannot be well ionized, which is a key factor for the low propellant utilization

Summary

Introduction

The Multi-cusped Field Thruster is a novel concept in electric propulsion, and it was investigated as early as 1962 by Janes et al.[1]. The thruster employs several alternating polarity permanent magnets to create periodic magnetic field. The electrons emitted from the cathode can reach the discharge channel along the magnetic field lines in the plume region, and some electrons are trapped by the multi-cusped magnetic field in the discharge channel. These electrons move back and forth with the competition between the mirror force and the electric field force in the cusped field. The generated ions are accelerated by the mainly axial electric field near the exit and spurted out of the thruster, forming the thrust.[2]

Methods

Results

Conclusion