For keeping microgravity level of microgravity and space science satellites, a kind of electric thruster, the radio-frequency ion thruster (RIT) has been designed and applied. The RIT produces thrust through ionizing neutral particles in the discharge chamber and extracting ions by the ion optics system. The length of discharge chamber affects the ionization of neutral particles as well as the performance of RIT. In this paper, an experimental study has been carried out for analyzing the influence of discharge chamber length. In the experiment, the RIT-5 with various discharge chamber lengths, 27.6 mm, 30.0 mm, 31.9 mm, 35.5 mm, 40.0 mm, has different performances under the same condition. With the same radio frequency power and propellant flow rate, the RIT-5 has the optimal performance in beam current and efficiency when the discharge chamber length is 30.0 mm or 31.9 mm.

中文翻译：

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放电室长度对5 cm射频离子推进器影响的实验研究

为了保持微重力和空间科学卫星的微重力水平，已经设计并应用了一种电动推进器，即射频离子推进器（RIT）。RIT通过使放电室中的中性粒子电离并通过离子光学系统提取离子来产生推力。放电室的长度会影响中性粒子的电离以及RIT的性能。在本文中，已经进行了实验研究以分析放电室长度的影响。在实验中，各种放电室长度（分别为27.6 mm，30.0 mm，31.9 mm，35.5 mm，40.0 mm）的RIT-5在相同条件下具有不同的性能。在相同的射频功率和推进剂流量下，