Research On The Principle And Experiment Of Helicon Plasma Thruster With Complex Propellant

With the development of manned spaceflight in China,it is of great significance to combine the problem of a large number of wastes generated by the long-term operation of the manned space station with the actual demand of attitude and orbit control for the space station.In recent years,Helicon plasma thruster?HPT?has attracted wide attention and become a new research hot spot in space propulsion field,with the characterictis of long life,high efficiency and so on.Therefore,H₂,CO₂ and CH₄,which were several gas components after the waste disposal of space station.The helicon plasma thruster with complex propellant were studied by the method of numerical simulation and experimental study,which layed a theoretical foundation and technical reserve for the application of complex working gas thruster for manned space station.The contents of this paper are as follows:The disadvantages of traditional electric propulsion for the use of space staion waste as propellant were discussed in this paper.Then,the research direction that helicon plasma thruster using waste gas as the propellant was proposed and analyzed.The feasibility of this research direction was pointed out according to the current research situation at home and abroad.This paper analyzed the high efficiency generation mechanism and plasma acceleration mechanism of helical plasma thruster.Basing on COMSOL finite element simulation software and taking the example of research method of the normal gas Ar,this paper studied the helicon discharge mechanism about the three gas components H₂,CO₂ and CH₄ after manned space processing.The effects of RF power,discharge pressure and magnetic induction intencity on plasma performance were all analyzed.So there were some suggestions for the experimental study of helicon plasma thruster using complex working gas.The experimental prototype of helicon plasma thruster was used to test the performance of plasma with Ar and CO₂ respectively.The effect of RF power on plasma parameters was studied by RF compensation probe.The experimental results showed that the reliable ignition could be achieved with Ar and CO₂ respectively,but the electron number density and specific impulse were lower and the thrust was smaller.The electron number density increased with the increase of RF power.Through the analysis of the experimental results,the improved scheme was put forward.The reason for the relatively low plasma density was that the RF power provided was too small to provide sufficient ionization energy for the working gas due to the limitation of the experimental conditions.Besides the test system and calculation method,Another reason why the specific impulse of plasma was too low was that the external magnetic field of the existing experimental prototype was defective,which was not conducive to the formation of double layer acceleration effect on the plasma.and it may even slow down the velocity of plasma to prevent it from accelerating out.In order to solve this problem,an improved design scheme for magnetic ciruit system was put forward.