Porous ionic liquid electrospray thrusters are the ideal propulsion technology for CubeSats because of their structural simplicity,high thrust accuracy and plume self-neutralization.The electrowetting technology can r...Porous ionic liquid electrospray thrusters are the ideal propulsion technology for CubeSats because of their structural simplicity,high thrust accuracy and plume self-neutralization.The electrowetting technology can replenish the propellant for the emitter online,thus prolonging the lifetime of the thruster.In order to gain a deeper understanding of its operating characteristics,the changes in thruster performance before and after propellant replenishment deserve to be scrutinized.In this study,the performance changes of a porous electrowetting ionic liquid electrospray thruster are tested by voltage-current test and time-of-flight mass spectrometry over a long operating time.The experimental results show that asymmetric operation with a negative current less than positive current for a long period of time causes anions to compensate for the emission after accumulation at the emitter,resulting in a phenomenon that the negative current is much larger than positive current.The reason for the difference in emission characteristics between the positive and negative modes is that the plume in the positive mode is quite ionized while the plume in the negative mode contains liquid droplets.This study provides a reference for the selection of operating conditions for ionic liquid electrospray thrusters.展开更多
射频离子推力器(Radio-frequency ion thruster,RIT)具有高比冲、长寿命、结构简单、性能灵活可调等优势,在无拖曳控制、卫星轨道及姿态控制、空间探测等领域具备广阔的应用前景。射频离子推力器通过栅极引出并加速离子产生推力,可通过...射频离子推力器(Radio-frequency ion thruster,RIT)具有高比冲、长寿命、结构简单、性能灵活可调等优势,在无拖曳控制、卫星轨道及姿态控制、空间探测等领域具备广阔的应用前景。射频离子推力器通过栅极引出并加速离子产生推力,可通过推力器羽流中的离子参数评估推力器的各项性能参数,推力器羽流离子参数的实验研究对推力器性能评估与优化具有重要意义。利用阻滞势分析仪与法拉第杯在不同输入条件下对射频离子推力器XRIT-200的羽流离子参数进行了实验研究。结果表明:推力器羽流中离子能量与屏栅电压成良好的线性关系,屏栅电压为1.3 kV时,离子能量达到1.3069 keV,但屏栅电压对推力密度的提升受到推力器工质流量的限制;同等屏栅电压与射频功率的条件下,推力密度随工质流量升高而增大;在给定的推力器输入条件下,射频功率升高,离子电流密度增大,推力器羽流发散角减小,推力器羽流更为集中。展开更多
基金co-supported by the National Key R&D Program of China(Nos.2020YFC2201103 and 2022YFB4601300)the National Natural Science Foundation of China(No.U22B20120)+1 种基金the Program of Beijing Engineering Research Center of Efficient and Green Aerospace Propulsion Technology,China(No.Lab ASP-2024-09)the Beijing Institute of Technology Research Fund Program for Young Scholars,China。
文摘Porous ionic liquid electrospray thrusters are the ideal propulsion technology for CubeSats because of their structural simplicity,high thrust accuracy and plume self-neutralization.The electrowetting technology can replenish the propellant for the emitter online,thus prolonging the lifetime of the thruster.In order to gain a deeper understanding of its operating characteristics,the changes in thruster performance before and after propellant replenishment deserve to be scrutinized.In this study,the performance changes of a porous electrowetting ionic liquid electrospray thruster are tested by voltage-current test and time-of-flight mass spectrometry over a long operating time.The experimental results show that asymmetric operation with a negative current less than positive current for a long period of time causes anions to compensate for the emission after accumulation at the emitter,resulting in a phenomenon that the negative current is much larger than positive current.The reason for the difference in emission characteristics between the positive and negative modes is that the plume in the positive mode is quite ionized while the plume in the negative mode contains liquid droplets.This study provides a reference for the selection of operating conditions for ionic liquid electrospray thrusters.
文摘射频离子推力器(Radio-frequency ion thruster,RIT)具有高比冲、长寿命、结构简单、性能灵活可调等优势,在无拖曳控制、卫星轨道及姿态控制、空间探测等领域具备广阔的应用前景。射频离子推力器通过栅极引出并加速离子产生推力,可通过推力器羽流中的离子参数评估推力器的各项性能参数,推力器羽流离子参数的实验研究对推力器性能评估与优化具有重要意义。利用阻滞势分析仪与法拉第杯在不同输入条件下对射频离子推力器XRIT-200的羽流离子参数进行了实验研究。结果表明:推力器羽流中离子能量与屏栅电压成良好的线性关系,屏栅电压为1.3 kV时,离子能量达到1.3069 keV,但屏栅电压对推力密度的提升受到推力器工质流量的限制;同等屏栅电压与射频功率的条件下,推力密度随工质流量升高而增大;在给定的推力器输入条件下,射频功率升高,离子电流密度增大,推力器羽流发散角减小,推力器羽流更为集中。
