著者
佐原 宏典 小林 悠也 中村 健二郎 尾又 由佳乃 阿部 圭典 染谷 昴 西尾 勘汰 飯塚 俊明
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 (ISSN:13446460)
巻号頁・発行日
vol.67, no.6, pp.205-210, 2019 (Released:2019-12-05)
参考文献数
20
被引用文献数
2

Microsatellites are now in vogue and a lot of and a variety of missions using them are progressed in the world, some of them require propulsion system to realize a highly precise attitude control or orbit transfer. In order to satisfy the requirements, we are developing Microsatellite-Friendly Multi-Purpose Propulsion System, MFMP-PROP, with capabilities of both mono-propellant and bi-propellant modes to provide both of small impulse bit and large delta-V, under the policies of Safety First, Border Free, Effective COTS, and Easy Scalability, based on the techniques of 60wt% Hydrogen Peroxide. We conducted captive tests of a thruster for mono-propellant mode under bi-propellant mode to confirm its stable ignition and continuous operation, and obtained performances under its pre-heating temperature and mixing ratio of hydrogen peroxide and ethanol, of 160 seconds of specific impulse at the highest.
著者
渡邉 力夫 林 浩平 岩尾 正樹 井河 恵大 冨田 信之
出版者
一般社団法人 日本航空宇宙学会
雑誌
宇宙技術 (ISSN:13473832)
巻号頁・発行日
vol.7, pp.45-52, 2008 (Released:2008-10-11)
参考文献数
9

When liquid nitrogen and heated water are mixed in a chamber, pressure increase due to evaporation expansion inside the chamber becomes high enough to generate thrust force for rocket propulsion. This thrust system is safer and environment-friendly compared to conventional rocket engines utilizing combustion process. This new type of rocket engine system is called "Water-Liquid Nitrogen rocket engine system" and it can be used for small payload mission with expected altitude of several kilometers. In this paper, experimentally obtained thrust characteristics are shown and analyzed. As a result, relations between the thrust force and the mixing chamber pressure are clarified. Also, it is found that the present injector can attain only half of the theoretically expected specific impulse due to insufficient mixing efficiency.
著者
大竹 智久 中江 雄亮 本橋 龍郎
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 (ISSN:13446460)
巻号頁・発行日
vol.55, no.644, pp.439-445, 2007 (Released:2007-10-10)
参考文献数
17
被引用文献数
29 64

Aerodynamic characteristics of NACA0012 airfoil at low Reynolds numbers (Re=1.0×104∼1.0×105) are measured systematically to clarify nonlinearity of the aerofoil characteristics. The variation of the lift curve with the angle of attack is divided into 5 sub-regions; the gradient of the lift curve much depends on the incident angle. Negative values of the gradient of lift coefficient are observed at lower angles of attack in a Reynolds numbers range. The sub-regions are summarized in a diagram of angle of attack and Reynolds numbers. The coefficients of drag and moment around 0.25 chord length have also unique characteristics.
著者
渡辺 力夫 冨田 信之 竹前 俊昭
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 (ISSN:13446460)
巻号頁・発行日
vol.51, no.593, pp.314-320, 2003 (Released:2003-09-26)
参考文献数
17
被引用文献数
2 2

The propulsive characteristics of water rockets are analyzed theoretically and experimentally. The unsteady thrust force acting on a PET bottle and the air pressure inside the bottle are measured simultaneously by the thrust test stand we have developed. The semi-empirical thrust history is obtained utilizing the air pressure history and it is compared with the measured thrust history. The results show qualitative agreement. The observation of the flow inside bottle by a high-speed video camera shows that the air precedes water when it is about to be discharged entirely. We have developed a flow regulator attached to the nozzle cap to reduce the precursor air discharge that is considered as a result of the swirling flow inside the bottle. The experimental results show that the air discharge and the body vibration are suppressed effectively.
著者
片山 雅之 外本 伸治 麻生 茂 平山 寛
出版者
一般社団法人 日本航空宇宙学会
雑誌
航空宇宙技術 (ISSN:18840477)
巻号頁・発行日
vol.19, pp.47-55, 2020 (Released:2020-03-14)
参考文献数
16

The effect of aerodynamic drag on loss of the velocity of a microsatellite on LEO is investigated and compared with the on-orbit data of two microsatellites, Hodoyoshi-1 of the University of Tokyo and QSAT-EOS of Kyushu University, which were launched in 2014. A new model, which includes the influence of the solar activities on atmospheric density, is introduced in this paper. The results obtained from the model suggest that the effect of solar activity on the atmospheric density has to be considered with the deviation of F10.7 parameter due to the number of sunspots. The model is applied to a microsatellite composed of a cubic main body and a deorbit sail to estimate its altitude change due to aerodynamic drag. The rotation of the satellite is taken into consideration.
著者
山名 正夫
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空学会誌 (ISSN:00214663)
巻号頁・発行日
vol.2, no.6, pp.108-112, 1954-03-31 (Released:2009-07-09)
参考文献数
3

Some of the wartime Japanese navy planes at their experimental stages were easily brought into accidental (or unintentional) autorotation in acrobatic flight such as vertical turn or loop. The analytical studies, refining procedures taken against these defects and design precautions are described here.When the wing is liable to stall at its tip or at the approximate middle portion between tip and root, and when the directional stability is not sufficient under large incidence angles, the accidental autorotation will happen due to small side slip angle ψ or angular velocity r around Z axis caused by a slight and unavoidable incoordination of control. The procedures are indicated in Fig. 5.Consequently it is summarized: that the stall of main wing should grow gradually outward from root and forward from trailing edge as indicated in the right half of Fig. 6 (a), that the value of ∂Cn/∂ψ should not decrease even under large incidence angles.
著者
上山 和夫 安部 正 杉木 勝昌 岡 雄生
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会誌 (ISSN:00214663)
巻号頁・発行日
vol.22, no.247, pp.405-408, 1974 (Released:2009-05-25)

A unique device, named "dihedral effect adjusting fin" is introduced in the development of Mitsubishi twin-turboprop business plane, MU-2G. This device, a fin attached to the wing tip tank, causes a modification of interference effect of wing tip tank with the main wing, and facilitates the adjustment with assurance of dihedral effect of an airplane with wing tip tank.In this note, the idea of dihedral effect adjusting fin and its application to the development of MU-2G plane are reviewed.