腔体结构参数对毛细管放电型脉冲等离子体推力器放电特性的影响  

Influence of cavity configuration parameters on discharge characteristics of capillary discharge based pulsed plasma thruster

作　　者：王亚楠[1] 任林渊 丁卫东[1] 孙安邦[1] 耿金越[2] Wang Ya-Nan;Ren Lin-Yuan;Ding Wei-Dong;Sun An-Bang;Geng Jin-Yue(State Key Laboratory of Electrical Insulation and Power Equipment,Xi’an Jiaotong University,Xi’an 710049,China;Beijing Institute of Control Engineering,Beijing 100190,China)

机构地区：[1]西安交通大学,电力设备电气绝缘国家重点实验室,西安710049 [2]北京控制工程研究所

出　　处：《物理学报》2021年第23期306-319,共14页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:52007147);中国博士后科学基金(批准号:2020M683480);北京控制工程研究所先进空间推进技术实验室和北京市高效能及绿色宇航推进工程技术研究中心开放基金(批准号:LabASP2020-07)资助的课题.

摘　　要：毛细管放电型脉冲等离子体推力器在微纳卫星在轨机动应用中具备良好的发展前景.本文系统研究了单次放电能量5 J条件下,不同毛细管腔体尺寸参数对推力器能量沉积特性、烧蚀特性、输出推力参数和等离子体羽流参数的影响规律.实验结果表明,增大毛细管腔体内径会显著降低放电电流密度,减小沉积能量和等效功率;增大腔体长度有助于提升能量传递效率.腔体结构尺寸变化影响单位面积沉积能量和管壁温度,进而改变烧蚀特性.当毛细管内径从1 mm增加至3 mm时烧蚀质量显著下降,随着腔体内径的进一步增大,等效烧蚀质量近似不变;烧蚀质量随毛细管长度的增加持续增大,但单位面积烧蚀质量不断下降.推力器元冲量取决于烧蚀质量与其等效速度,烧蚀特性的差异进一步影响腔体内等离子体密度和等效压强,影响等离子体电热加速过程.毛细管腔体内径和长度的不断增加,使得加速过程滞后于放电和烧蚀过程,作用于加速过程的电弧沉积能量比例降低,降低推力器等离子体喷射速度,元冲量减小,比冲降低,总体效率下降.结合总体效率传递模型分析,毛细管内径对推力器效率的影响主要体现在能量传递效率方面,毛细管长度变化主要影响等离子体电热加速效率,优化推力器总体效率需要从能量沉积效率和加速效率两方面入手.Capillary discharge based pulsed plasma thrusters have great prospects of applications in in-orbit maneuvering of micro-nano satellites.In this paper,the influence of different capillary cavity structure parameters on the thruster's energy deposition process,ablation characteristics,output thrust parameters and plasma plume parameters under an energy level of 5 J were studied.The experimental results indicate that the increase of the inner diameter of the capillary cavity will significantly reduce the discharge current density,which leads the deposition energy and equivalent power to decrease;the increase of the cavity length helps to improve the energy transfer efficiency.The influence of cavity structure on the ablation characteristics is reflected in the influence of deposition energy per unit area on the tube wall temperature.When the inner diameter of the capillary increases from 1 mm to 3 mm,the ablation mass decreases significantly,and then the equivalent ablation mass remains approximately unchanged as the inner diameter of the cavity increases further;the ablation mass continues to increase as the capillary length increases,while the ablation mass per unit area continues to decrease.The impulse bit depends on the ablation mass and plasma plume velocity,and the difference in ablation characteristic further affects the plasma in the cavity.The density and equivalent pressure determine the plasma electrothermal acceleration process.The continuous increase in the diameter and length of the capillary cavity will induce the acceleration process to lag behind the discharge and ablation process.And the decrease of the deposited energy impedes the electrothermal acceleration process,which results in the decrease of the impulse bit,specific impulse,and the overall efficiency.Furthermore,the overall efficiency transfer model analysis indicates the influence of the capillary inner diameter on thruster efficiency is mainly reflected in the energy transfer efficiency,and the capillary length change mainly affects the

关 键 词：脉冲等离子体推力器 毛细管放电 腔体结构 等离子体加速 

分 类 号：V439.2[航空宇航科学与技术—航空宇航推进理论与工程]