聚焦磁场及发散磁场对霍尔推力器壁面侵蚀的影响研究

Effects of Focusing and Diverging Magnetic Field Topology on Hall Thruster Channel Wall Erosion

关键词:  霍尔推力器  磁场位型  壁面侵蚀  寿命

Key words:  Hall thruster  Magnetic field topology  Wall erosion  Lifetime

摘要:

为了研究磁场对霍尔推力器壁面侵蚀的影响，利用轮廓仪测量霍尔推力器内外壁面工作30h的侵蚀状况，对比聚焦磁场和发散磁场条件下的推力器壁面侵蚀过程，分析了聚焦磁场改善壁面侵蚀的方式和程度，并进行了机理分析。实验结果表明:在经过30h的实验后，聚焦磁场相对于发散磁场内陶瓷壁面侵蚀深度降低33%，外陶瓷壁面侵蚀深度降低18.6%。理论分析表明:在羽流发散半角小于30°以内时，溅射系数随羽流发散半角增大而增大，将羽流发散半角控制在小于30°以内的“磁聚焦”模式，能够有效降低离子对壁面的侵蚀，进而可提高推力器寿命。

Abstract:

In order to study the effects of magnetic field on hall thruster channel wall erosion，contourgraph is utilized to measure the erosion status of inner and outer wall after Hall thruster works for 30h. The wall erosion process of thruster is compared under focusing magnetic field and diverging magnetic field conditions. The method and intensity of improving wall erosion by focusing magnetic field are analyzed，and the mechanical analysis is performed. The experimental results show that after 30h experiment，compared with diverging magnetic field，the erosion depth of interior ceramic wall is reduced by 33% under focusing magnetic field conditions，and the erosion depth of exterior ceramic wall is reduced by 18.6%. The theoretical analysis shows that when the plume divergence half-angle is below 30°，the sputtering yield increases with the increase of plume divergence half-angle. The magnetic focusing mode that the plume divergence half-angle is controlled to be below 30° can effectively reduce the erosion to wall caused by ions，which will improve the thruster life.