Research On Discharge Characteristics Of Miniaturized Cusped Field Thruster

In recent years,deep space exploration missions have attracted people’s attention.In deep space exploration missions,drag-free control technology is sometimes needed to accurately compensate non-conservative forces in real time.Because of its special working principle,the cusped field thruster has the characteristics of large range of adjustable thrust,long life and multiple working modes.It is an ideal thruster for drag-free control.Although the cusped field thruster has many advantages,it must be miniaturized in order to achieve the performance requirements of low power and high precision.In the process of radial miniaturization,the areato-volume ratio of the cusped field thruster will inevitably increase,and the discharge characteristics of the thruster will also change.In this paper,the Particle-in-Cell method is used to study the discharge characteristics of the cusped field thruster.According to the distribution of particles,the discharge characteristics of the cusped field thruster when the area-to-volume ratio increases are studied,and the main factors that promote the change of the discharge characteristics of the cusped field thruster are analyzed.Subsequently,due to the increase of area-to-volume ratio,the problems of wall effect enhancement and specific impulse decrease of thrusters were studied respectively.To solve the problem of increasing the wall effect of the thruster,the discharge characteristics of the thruster with different wall materials were simulated numerically,and the wall materials with appropriate secondary electron emission coefficient were selected to effectively reduce the wall effect,so as to ensure a good working life of the cusped field thruster.In order to solve the problem of reducing the specific impulse of thruster,the replacement working medium krypton with higher specific impulse was selected,and the discharge characteristics of krypton were studied.Through simulation,it was found that using krypton could effectively improve the problem of specific impulse reduction in radial miniaturization of the cusped field thruster.