冷气推力器泄漏机理分析及改进  

Analysis for Leakage Mechanism of a Cold Gas Thruster and its Improvement

作　　者：高永[1,2] 宋飞 武葱茏[1,2] 胡越欣 林倩[1,2] 陈芳浩 GAO Yong;SONG Fei;WU Conglong;HU Yuexin;LIN Qian;CHEN Fanghao(Beijing Institute of Control Engineering,Beijing 100190,China;Beijing Engineering Research Center of Efficient and Green Aerospace Propulsion Technology,Beijing 100190,China;DFH Satellite Co.Ltd.,Beijing 100094,China)

机构地区：[1]北京控制工程研究所,北京100190 [2]北京市高效能及绿色宇航推进工程技术研究中心,北京100190 [3]航天东方红卫星有限公司,北京100094

出　　处：《真空科学与技术学报》2021年第12期1208-1212,共5页Chinese Journal of Vacuum Science and Technology

基　　金：科技部国家重点研发计划(2020YFC2201101);科技部国家重点研发计划(2020YFC2201002)。

摘　　要：针对某冷气推力器在总装测试时出现的泄漏故障,采用压力真空法开展了推力器漏率复测,结果表明该推力器内漏率超标。产品分解后对推力器零组件的损伤及多余物等情况进行检查,发现推力器阀门非金属(聚四氟乙烯)密封面的环形密封接触凹痕内部存在一道贯穿性伤痕;经扫描电镜测量,伤痕造成的微小通道长度约220μm,直径约13.7μm。采用分子流漏率计算公式对该通道造成的泄漏率进行计算,结果显示非金属密封面贯穿性伤痕通道产生的漏率值为5.1×10^(-5)Pa·m^(3)/s,与压力真空法测得漏率值相符合。在此基础上,总结出多余物填堵密封面、密封面伤痕和阀芯偏斜等三种典型的阀门内漏故障模式,比较分析了不同故障模式下密封面的形态特征,提出了相应的检测改进措施。To diagnose the leakage fault of a cold gas thruster during the satellite’s assembly test,the leak rate of the thruster is retested by pressure vacuum method.Test results indicate that the leak rate of the thruster exceeds the required value.A penetrating scratch inside the contact notch of the non-metallic polytetrafluoroethylene(PTFE)sealing surface of the thruster valve is found through morphology analysis after disassembling the thruster.Dimensional measurements of the scratch channel by scanning electron microscope show that the length of the scratch channel is 220μm and the diameter is 13.7μm.Calculated leak rate caused by the scratch channel using molecular flow theory is 5.1×10^(-5)Pa·m^(3)/s,which is consistent with the value measured by pressure vacuum method.Three typical valve leak modes and their morphological characteristics are summarized,including sealing surface plugged by residues,penetrating scratch in sealing surface and deflection of valve plug.Accordingly,methods for detection and improvement are proposed.

关 键 词：冷气推力器 形貌分析 泄漏 分子流 

分 类 号：V437[航空宇航科学与技术—航空宇航推进理论与工程]