Research On The Influence Of Magnetic Field And Grid Structure On The Discharge Peformance Of Ion Thruster

Although the current aerospace science and technology is developing rapidly,it is necessary to down to earth,and promote the aerospace science and technology to move forward steadily to get into deeper space.This paper mainly studies the performance improvement of ion thruster used to explore deep space,and focuses on the magnetic field structure in the discharge chamber of the ion thruster and the influence of the gate structure of the thruster on the performance of the thruster,so as to obtain the ion thruster whose magnetic field and gate structure schemes with improved performance.For the study of the relationship between magnetic structure and discharge performance of the traditional Kaufman ion thruster,this paper doesn't design and conduct a numerical simulation experiment simply using the relationship of magnetic induction and plasma to get how magnetic structure to do with discharge performance of ion thruster,but starting from the mathematical model of the spatial magnetic field distribution generated by the permanent magnet,two key parameters that affect the spatial magnetic field distribution of the thruster discharge chamber are obtained,the cross-sectional dimension of the magnetic ring and the magnitude of the magnetization intensity.Design and carry out numerical simulation experiments with these two key parameters as driving variables.The results show that the volume of the magnetic-field-free area in the discharge chamber has a maximum value as the changing of the size of the magnetic ring,and in this case also corresponds to the maximum thrust and the minimum discharge loss.For the effect of the magnetic ring magnetization on the discharge performance,within the simulated calculation range,the volume change of the field-free area is not obvious,and the thrust generated by the thruster shows a gradual increase.The annular ion thruster is a new concept ion thruster with greater thrust and higher impulse.At present,the research on the discharge performance of the annular ion thruster are relatively few.In this paper,the numerical simulation experiment is designed for the characteristics of the hollow cathode bias of the thruster,and the influence of the channel width of the discharge chamber on its discharge performance is systematically investigated.Thus,three sets of numerical simulation experiments are designed and carried out separately under the condition that three key variables are fixed: the outdoor diameter of the initial configuration,the bottom anode wall area of the initial configuration,and the anode area of the side wall of the initial configuration.According to the results of three sets of numerical simulation experiments,the optimization space is further shrunk,and the influence of the bottom anode wall,theside anode wall and the discharge chamber channel width on the discharge performance of the annular ion thruster is shown.Finally,a set of numerical simulations using the eccentric magnetic rings is designed and implemented.The results show that the eccentric design of the magnetic ring in the discharge chamber can alleviate the ion offset distribution to a certain extent caused by the hollow cathode bias.The effect of the gate structure on the discharge performance of the thruster is studied.The gate combination structure is adjusted by adjusting the spacing between the screen grid and the acceleration grid,accelerating grid and the deceleration grid.Numerical simulation experiments were carried out on three different plasma densities,then we can obtain the improved discharge performance indexes such as beam current and potential distribution through the grid hole,single-hole beam current,inrush current and beam focusing state.