IEEE Transactions on Applied Superconductivity 32(6) 1-5 2022年 査読有り
The critical heat flux in liquid hydrogen is ten times higher than that in liquid helium and is approximately half of that in liquid nitrogen. Since the resistivity of pure metal such as copper or silver at 20 K is less than one-hundredth of that at 300 K, HTS magnets immersed in liquid hydrogen are expected to satisfy the fully cyostable condition or to be stable against high resistive heat generation enough for quench detection at a practical current density. In order to examine cryostability of HTS magnets in liquid hydrogen, a pool-cooled Bi2223 magnet with a 5 T magnetic field at 20 K has been designed, fabricated and tested in liquid nitrogen prior to excitation tests in liquid hydrogen. The magnet consists of six outer double pancake coils with the inner diameter of 0.20 m and four inner double pancake coils with the outer diameter of 0.16 m. The resistive voltage to initiate thermal runaway in the coil as-sembly in liquid nitrogen was higher than 1 V that is sufficient high for quench detection.
令和4年度宇宙輸送シンポジウム: 講演集録 = Proceedings of Space Transportation Symposium FY2022 2023年1月
令和4年度宇宙輸送シンポジウム(2023年1月12日-13日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)) , 相模原市, 神奈川県
Space Transportation Symposium FY2022 (January 12-13, 2023. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan
資料番号: SA6000184015
STCP-2022-015
First flight testing of Balloon-based Operation Vehicle (BOV) was carried out in 2006 and succeded. Second flight testing with a wing-body configuration will be done by a high-altitude balloon and dropped in September, 2006. Various types of onboard experiments such as a microgravity experiment and a demonstration of a supersonic engine are planned during flights for the third, fourth, and fifth flights. The aerodynamics load and characteristics of BOVs have been obtained by the CFD simulations as well as by the wind tunnel testing in ISAS. In this paper, the numerical simulations for BOV are presented and the results showed that the non-linear interaction between the wings, body, and engine exists for high angle of attack.