不同工质对MPT启动与稳定工作影响的研究

【作者】 宋军；

【导师】 毛根旺；

【作者基本信息】 西北工业大学 ， 航空宇航推进理论与工程， 2004， 硕士

【摘要】 近年来，随着对航天器推进系统性能要求的不断提高，电推进以其独有的优势引起了航天界的兴趣和重视，并越来越多的被应用到空间任务中。微波等离子推力器（MPT）是一种新型的电热型推力器，它具有比冲高、寿命长、羽流污染小等优点，具有广阔的应用前景。 目前，主要的电推力器都进行了不同工质的实验研究，对工质的优化选择直接决定了MPT的性能和应用前景。本文对不同的推进工质进行MPT点火启动实验及真空稳定工作实验研究，并对结果进行分析、比较和研究，最终为MPT工程应用寻找最合适的推进工质。 论文的工作和新见解主要包括： 1 在设计状态和工作状态下，根据MPT的实验参数，对MPT使用不同工质时的性能进行了工程估算，这对MPT现阶段的实验研究和今后的研究有重要的指导意义； 2 对于He、Ar推进工质，讨论微波的接头材料、探针与内导体的间隙、内导体的位置、微波的输入功率、工质的质量流量以及环境真空度对MPT真空启动和稳定工作的影响，并探讨微波的输入功率、工质的质量流量对谐振腔压强、推力、反射功率以及谐振腔温度的影响； 3 对于N₂、H₂、NH₃、H₂O推进工质，主要讨论与He、Ar工质不同的特性，并从长远的眼光和工程应用的角度，认为其可行性不容置疑，潜在优势不可忽略，是未来MPT应用的主流推进工质。 研究表明，对于MPT的探索性研究，He、Ar是两种适宜的推进工质，启动方便、工作稳定，特别有利于MPT的早期研究；但是从长远的眼光和工程应用的角度，N₂、H₂、NH₃、N₂H₄以及H₂O等作为MPT的推进工质，其潜在优势令人鼓舞。更多还原

【Abstract】 With incessant requirements for high performance of spacecraft propulsion system, Electric Propulsion (EP) has become a focus of spaceflight field recently because of its particular advantages. Microwave Plasma Thruster (MPT) is a new type of electro-thermal thruster, which has widely applied prospect because of its high specific impulse, long lifetime, low plume contaminant and so on.So far, some electric thrusters have been made experiments on different propellants. Selecting optimum propellant determines the performance and the prospect of application of MPT. This paper aimes to accomplish ignition start-up and steady work experiments in vacuum environment using different propellant and to find optimum propellant for engineering application of MPT finally based on analyzing, comparing and researching the experimental results.The contents and new views of this paper include:1. According to the experimental parameters of MPT, the main performance parameters of different propellants have been given by engineering performance computation under designed and working states, which has great importance for the experimental research and the future work.2. For Helium and Argon, the factors which influence on MPT’s vacuum steady work have been discussed such as the material of microwave tie-in, the distance between the probe and inner-conductor, the position of the inner-conductor, the input power of microwave, the mass flowrate of propellant and the vacuum pressure of environment, and the influence has been discussed of the microwave power and the mass flowrate of propellant on the pressure of the resonance cavity, thrust, reflected power and the temperature of the resonance cavity.3. For Nitrogen, Hydrogen, Ammonia and Vapour, the difference has been discussed between its and Helium and Argon. Based on a long time viewpoint and the engineering application, the feasiblity can’t be suspected and the potential advantages can’t be ignored which are major propellant for the MPT’s research in the future.For MPT, Helium and Argon are appropriate propellants, which are suitable for the initial research of MPT. The experiments prove that MPT can start up easily and operate steadily. However, based on a long time viewpoint and the engineering application, MPT should apply such propellants as Nitrogen, Hydrogen, Ammonia, Hydrazine and Vapour.更多还原