摘要
10 cm电子回旋共振离子推力器(ECRIT)的ECR中和器是关键部件,其内部磁场是影响中和器性能的重要因素.磁场的均匀性和磁阱位置是磁场特征的重要表现,制约等离子体与电势的分布规律、电子引出过程及中和器性能.本文分别建立磁场均匀性低、磁阱位于电子引出孔上游和磁场均匀性高、磁阱位于电子引出孔下游的ECR中和器PIC/MCC模型,在给定参数条件下,开展等离子体和电势分布规律及电子引出过程的数值模拟研究并分析其对中和器性能的影响.结果表明,磁场均匀性高、磁阱位于电子引出孔下游时,中和器内整体电势分布较均匀,电子容易朝磁阱区迁移,低引出电势引出高电子束流,其性能高于磁场均匀性低、磁阱内置的中和器.研究工作将为发展高性能的ECR中和器奠定重要基础.
Electron cyclotron resonance(ECR)neutralizer is a key component of electron cyclotron resonance ion thruster(ECRIT)with a diameter of 10 cm,which plays an important role in maintaining the spacecraft potential balance and neutralizing the ions in the plume region.Optimizing magnetic field distribution is an important way to improve the performance of neutralizer.At the same time,the uniformity of the magnetic field and the position of the magnetic trap can affect the magnetic field characteristics,plasma performance,electron extraction process,and beam current.Previous experimental researches showed that the beam current extraction performances of the two ECR neutralizers with different magnetic field uniformity and different magnetic trap locations are significantly different.However,it is difficult to reveal the physical phenomena and causes only through experiments,so numerical simulation is needed.Therefore PIC/MCC codes for the ECR neutralizers with different uniformity of magnetic field and different positions of magnetic trap are established.Under the given electron extraction potential,numerical simulations are accomplished to study electron extraction procedure and analyze its influence on the performance of the neutralizer.The simulation results show that when the magnetic field uniformity is low and the magnetic trap is located upstream of extraction orifice,the migration of electrons from the magnetic trap to the outlet is limited by the magnetic field and the electric field,thus a higher potential energy is needed to extract the electrons.Otherwise,when the magnetic field uniformity is high and the magnetic trap is located at the downstream of extraction orifice,electrons will be more likely to migrate towards the magnet trap.After the electrons reach the magnetic trap,under the action of the anode potential,the external potential is higher,and the external weak magnetic field almost fails to hold these electrons.Therefore a large number of electrons can be extracted at low extraction potential.This
作者
罗凌峰
杨涓
耿海
吴先明
牟浩
Luo Ling-Feng;Yang Juan;Geng Hai;Wu Xian-Ming;Mou Hao(School of Astronautics,Northwestern Polytechnical University,Xi’an 710072,China;Science and Technology on Vacuum Technology and Physics Laboratory,Lanzhou Institute of Physics,Lanzhou 730000,China)
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2024年第16期181-189,共9页
Acta Physica Sinica
