电子温度各向异性对霍尔推力器中等离子体与壁面相互作用的影响  

Effect of electron temperature anisotropy on plasma-wall interaction in Hall thruster

作　　者：卿绍伟[1,2] 鄂鹏[1] 段萍[3] 

机构地区：[1]哈尔滨工业大学电气工程系,哈尔滨150001 [2]重庆大学动力工程学院,重庆400030 [3]大连海事大学物理系,大连116026

出　　处：《物理学报》2012年第20期303-309,共7页Acta Physica Sinica

基　　金：中央高校基本科研业务费(批准号:0903005203189);国家自然科学基金(批准号:11005025;10975026);哈尔滨工业大学科学研究创新基金(批准号:HITNSRIF2009044);辽宁省科学技术计划重点项目(批准号:2011224007)资助的课题~~

摘　　要：为进一步揭示霍尔推力器放电通道饱和电子温度高达50—60 eV的原因,利用二维粒子模拟方法研究了霍尔推力器中电子温度各向异性对等离子体与壁面相互作用的影响,统计了等离子体与壁面相互作用的重要物理量,如电子与壁面的碰撞频率、通道电子在壁面的能量沉积及二次电子对通道电子的冷却.结果表明,当电子温度较低时,电子温度各向异性对等离子体与壁面相互作用的影响较小;当电子温度大于24 eV时,等离子体与壁面相互作用明显增强,并且电子温度各向异性会显著地降低电子与壁面的碰撞频率,减小电子在壁面的能量沉积,减弱鞘层对通道电子的冷却效应.电子温度的各向异性通过减弱通道电子与壁面的相互作用,有利于提高霍尔推力器放电通道的饱和电子温度.To further reveal the physical mechanism of the saturated electron temperature which is about 50--60 eV in the discharge channel of Hall thruster, the effect of electron temperature anisotropy （ETA） on plasma-wall interaction in Hall thruster is studied by using a 2D3V particle-in-cell sheath dynamic model. Some important physical parameters such as electron-wall collision frequency, electron energy deposition at wall and the cooling effect of near-wall sheath on channel electron are calculated. Numerical results indicate that the influence of ETA on plasma-wall interaction is neglectable when electron temperature is low. However, when Te 〉 24 eV, the ETA can significantly reduce electron-wall collision frequency, thereby reducing the electron energy deposition at wall and weakening the cooling effect of near-wall sheath on channel electron. It suggests that the anisotropy of electron temperature tends to increase the saturated electron temperature in the discharge channel of Hall thruster through remarkably weakening the interaction between channel electron and wall.

关 键 词：霍尔推力器 电子温度各向异性 等离子体与壁面相互作用 粒子模拟 

分 类 号：O53[理学—等离子体物理]