宇宙科学広報・普及主幹付

今井 駿

イマイ シュン  (Shun Imai)

基本情報

所属
国立研究開発法人宇宙航空研究開発機構 宇宙科学研究所 研究開発員

研究者番号
90935107
ORCID ID
 https://orcid.org/0000-0002-1056-4841
J-GLOBAL ID
202101017728385182
researchmap会員ID
R000026820

研究キーワード

 2

論文

 10
  • 山田和彦, 小野稜介, 八木邑磨, 中尾達郎, 髙栁大樹, 杉本諒, 久保田笙太, 丸祐介, 小澤宇志, 永田靖典, 今井駿, 永井大樹, 森英之
    宇宙航空研究開発機構研究開発報告: 大気球研究報告 JAXA-RR-23-003 77-104 2024年2月  査読有り
  • IMAI Shun, WATANABE Hiroki, MATSUNAGA Yoshiki, IMAGUCHI Daisuke, ONISHI Nobuhito, FUNAKI Ikkoh
    Journal of Evolving Space Activities 1 n/a 2023年  査読有り筆頭著者
    This paper reports on our study to develop a magnetic circuit with a discrete outer coil and test its performance in a Hall thruster. The results were compared to those of a Hall thruster on board the Engineering Test Satellite-9 (ETS-9), which used a cylindrical outer coil. At the normalized magnetic field strength of 0.58 for the 6 kW operation using a six poles discrete outer coil, the thrust, discharge current, Isp, thrust-to-power ratio, thrust efficiency, and discharge oscillation were 386.7 mN, 19.0 A, 1890 s, 66.9%, 62.0%, and 13.5% respectively. The Hall thruster with the new magnetic circuit achieved equivalent performance (including discharge stability) to the Hall thruster on board the ETS-9. Further, the study investigated the effect of the number of poles on the performance of the Hall thruster: the performance with the three pole coil was lower than that with the six poles coil. This paper also reports on the effect of pole numbers on utilization efficiency. Mass and current utilization efficiency were more affected by the magnetic field generated by the three poles outer coil.
  • Tatsuro Nakao, Kazuhiko Yamada, Hitoshi Hamori, Takahiro Ishimaru, Shun Imai, Yasunori Nagata, Kaho Maeda, Kenji Maehara, Hiroto Habu, Yuki Akimoto, Minami Mori, Marie Mitsuno, Koshiro Hirata, Hideto Takasawa, Kojiro Suzuki
    26th AIAA Aerodynamic Decelerator Systems Technology Conference 2022年5月16日  
  • 永田 靖典, 中尾 達郎, 羽森 仁志, 石丸 貴博, 今井 駿, 秋元 雄希, 山田 和彦
    日本航空宇宙学会論文集 70(6) 234-241 2022年  
  • IMAI Shun, IMAGUCHI Daisuke, WATANABE Hiroki, KUBOTA Kenichi, CHO Shinatora, OSHIO Yuya, FUNAKI Ikkoh
    TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES 65(1) 1-10 2022年  査読有り筆頭著者
    <p>The ion energy angle distribution and its relationship to plasma parameters for spot and plume modes are elucidated for a LaB6 hollow cathode with a radiative heater. Measurements were conducted using a retarding potential analyzer (RPA) and a single Langmuir probe. The ion energy distribution function (IEDF) characteristics showed different tendencies in the current density and mass flow-rate dependence under different plasma modes. The IEDF peak potential for the spot mode varied from 16 to 23 V with increasing current density, and the IEDF peak potential for the plume mode varied from 16 to 32 V with decreasing mass flow rate. Considering angle dependency of ion energy, when the observation angle was changed from the radial direction to the axial direction, the IEDF peak potential increased from 29 to 40 V for the plume mode (10 A, 10 sccm) and increased slightly from 16 to 18 V for the spot mode (20 A, 30 sccm). The probe measurement analysis revealed that the IEDF peak energies are the same as, or exceed, the plasma potential and have a qualitative correlation with the electron temperature spatial distribution.</p>

MISC

 29

講演・口頭発表等

 22

所属学協会

 2