著者
山川 宏 小川 博之 藤田 和央 野中 聡 澤井 秀次郎 國中 均 船木 一幸 大津 広敬 中山 宜典
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.52, no.603, pp.148-152, 2004 (Released:2004-05-31)
参考文献数
4
被引用文献数
5 6

A magneto-plasma sail produces the propulsive force due to the interaction between the artificial magnetic field around a spacecraft inflated by the plasma and the solar wind erupted from the Sun. The inflation of the magnetic field by the plasma was proposed by a group of the University of Washington and the basic research has just started. This paper summarizes the characteristics of the magneto plasma sail by comparing with the other low-thrust propulsion systems, and investigates its potential application to near future planetary missions. Finally, an engineering satellite to demonstrate the magneto-plasma sail is proposed as a first step.
著者
羽生 宏人 和田 英一 丹羽 崇博 近藤 靖雄 川村 尚史 丸山 信也 岡村 彩乃 山科 早英良 永井 康仁 中道 達也 上道 茜 田中 成明 小林 直樹 笠原 次郎 森田 泰弘
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.9, pp.15-21, 2010 (Released:2010-05-14)
参考文献数
6
被引用文献数
1

The educational hybrid-rocket was successfully launched and it also landed within the predicted area. Aerodynamic characteristics of the rocket designed by students of Tsukuba University were evaluated by the wind tunnel testing with the support of Tokai University. The flight path affected by the environmental condition, especially wind direction and velocity, was simulated with the original calculation program. The altitude of the rocket was measured with the optical equipment and the apex was 123 m although the calculation indicated 198 m. We expected that the insufficient filling or the volatilization of Nitrous oxide as an oxidizer led to this result. And then, the apex was verified with a function of the oxidizer filling ratio. The results showed that 81.2 % of the oxidizer volume in comparison with the firing test condition was accumulated in the tank at the launch.
著者
山田 剛治 鈴木 俊之 高柳 大樹 藤田 和央
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.57, no.670, pp.426-436, 2009 (Released:2009-11-25)
参考文献数
22
被引用文献数
1 1

A free piston double diaphragm shock tube with 70 × 70mm cross-section at test section was newly developed for the purpose of investigating nonequilibrium phenomena behind a shock wave. This paper presents the performance of the shock tube and the measurement system newly developed. Experimental investigation to clarify its characteristics was conducted for various operational parameters, such a rupture pressure of the first diaphragm and initial pressures of the low pressure tube, the high pressure tube, and the compression tube. Based on the characteristics experiment, a performance map of the shock tube was obtained by changing the operation parameters. The result shows that the shock tube is capable of generating the shock layer corresponding to the super orbital reentry flight conditions. The newly developed measurement system enables us to obtain the spatial distribution of spectra behind a shock wave with high spatial and time resolution. A description of the measurement system and typical examples of the measured spectra are presented.
著者
海老沼 拓史 中須賀 真一
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.54, no.635, pp.542-548, 2006 (Released:2006-12-25)
参考文献数
9
被引用文献数
2 2

An increasing number of small satellites and hybrid rockets are proposed for miscellaneous space applications, many of which assume the use of Global Positioning System (GPS) for positioning. Some of those platforms are designed and developed by university students and require very low power consumption and also low cost. This paper describes the adaptation of small GPS receivers and open source receiver firmware for space and high dynamics applications, including software performance validation using a GPS signal simulator.
著者
麻生 茂 谷 泰寛
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.66, no.1, pp.18-24, 2018-01-05 (Released:2018-01-05)
参考文献数
24

本稿では,エアタクシーやジェネラルアビエーションへの用途を目的として小型電動航空機の開発機運が急速に高まっていることを示し,現在,世界中で研究開発が始まっている電動航空機を紹介している.また,日本航空宇宙学会航空ビジョン委員会のグリーンイノベーションの提言として電動航空機が挙げられていることを示すとともに,著者らの小型電動航空機に対する研究開発の試みとして,小型電動航空機のコンセプト機の提案と1/10スケール機の試作に関する試み,EV車用などに開発された電気モーターとリチウムイオンバッテリーを組み合わせた電動パワーユニットの開発とそれを小型機に搭載しての走行テスト,電動航空機用に特化した概念設計手法の開発を紹介している.最後に,高い利便性を有する小型電動航空機の出現が交通インフラに革命をもたらすことを述べている.
著者
井藤 創 本田 博一
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.58, no.679, pp.226-232, 2010 (Released:2010-08-27)
参考文献数
19

This paper describes results of an exploratory study to investigate the capability of a passive approach for controlling the characteristic spanwise length of Görtler vortices generated in hypersonic flows: a serrated leading edge. Heat transfer, pressure measurements, encapsulated thermochromic liquid crystal, schlieren and glow spark visualizations were conducted with a flat plate/ramp model whose leading edge had a triangular wave shape in a gun tunnel at Mach number 10. Effect of wavelength Λ of the triangular waves on downstream flows was studied. Aerodynamic heating patterns observed with the liquid crystal confirmed that the vortex wavelength was equal to Λ. This was also supported by the spark results that filamentary bright lines perpendicular to an installed line-anode parallel to the spanwise direction at the ramp surface emerged at intervals of Λ. Phase lag was observed only between heat transfer data measured in the spanwise direction, which suggests that the vortex structure existed in the reattaching boundary layers. Pressure distribution in the streamwise direction was similar among all of the Λ tested. In contrast, the heat transfer data points exhibited a large scatter and the peak heating value for the finite Λ was somewhat larger than that for the infinite Λ. Schlieren results indicated that the appropriate Λ can mitigate flow separation.
著者
手塚 亜聖 砂田 保人 李家 賢一
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 = Journal of the Japan Society for Aeronautical and Space Sciences (ISSN:13446460)
巻号頁・発行日
vol.57, no.665, pp.258-265, 2009-06-05
参考文献数
20
被引用文献数
5

In the Reynolds number region lower than approximately 1.0 × 105, which corresponds to the Reynolds number region of a Micro Air Vehicle, thinner and sharper leading edge airfoil performs better than thicker and blunter one. This research focuses on the difference in flowfields which are clarified by means of streamline calculation and surface pressure distribution measurement. Numerical studies were performed to the blunt type NACA0012 airfoil and both numerical and experimental studies were performed to the thinner type 4% cambered-plate airfoil. The performance of the NACA0012 airfoil is deteriorated with decreasing Reynolds number, whereas that of the 4% circular arc cambered-plate airfoil is not affected. The deterioration of the NACA0012 airfoil performance is mainly due to the laminar boundary layer separation near the trailing edge; such phenomena are not essential to the performance in the cambered-plate airfoil results. This paper also demonstrates that the flow separation at the trailing edge can be estimated from the temporal amplification factor of the oscillatory mode which is calculated by the global linear stability analysis.
著者
高橋 教雄 朝倉 博幸
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.63, no.1, pp.11-13, 2015

降着装置システムは安全に地上から離れ安全に地上に降りることに加えて地上では離着陸,速度制御,操向角制御タキシング等を行う装置であることから軽量・コンパクトで高い信頼性のあることが要求される.このために古くに確立された技術が現在も引き継がれているが,近年の航空機電動化技術は確実に降着装置システムにも適用範囲を広げている.飛行制御系統に適用されているEHA(Electro Hydrostatic Actuator)やEMA(Electro Mechanical Actuator)を中心にして従来の集中油圧方式の置き換えによる航空機全体の軽量化と,エネルギー利用の効率化は自動車の電動化技術に類似した動きと捉えても良いように思える.ここでは,降着装置システムの電動化技術の端緒となったボーイング787に採用された電動式ブレーキと,近年開発が進められている電動タキシング技術について紹介するとともに,日本で開発を進めている降清装置の電動化研究についても触れながらエアラインの視点を含めて紹介する.
著者
池田 健
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.17, no.181, pp.61-63, 1969 (Released:2009-05-25)
参考文献数
2
被引用文献数
1

Actual rocket bodies have a finite bending stiffness. Low bending stiffness reduces the pitching moment of the body in comparison with the case where the rocket body is assumed to be rigid and this tendency becomes stronger as the velocity increases. This paper treats the case of the single step rocket of finite bending stiffness and gives an approximate equation of the righting pitching movent. This approximation is expected to be also applicable to multi-step rockets.

1 0 0 0 OA 宇宙炉の現在

著者
金子 義彦
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.44, no.515, pp.681-690, 1996-12-05 (Released:2010-12-16)
参考文献数
14
著者
満武 勝嗣 東野 伸一郎
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.58, no.677, pp.153-163, 2010 (Released:2010-07-23)
参考文献数
10
被引用文献数
3 5

The authors have proposed the A*-EC hybrid path planning method which can generate a 3D flight path quickly considering terrain and obstacle avoidance. This paper proposes two methods to improve its calculation time in order to apply it to a larger scale problem in real time. Using the two methods, the calculation time reduces approximately from half to quarter. The authors measure the calculation times to examine the performance of the improved A*-EC method by changing the number of waypoints and ``nodes'' which are the apexes of the 3D cells expressing terrain and obstacles. Calculation time is about 10—100 seconds in case of 50—100 waypoints and 2000—7500 nodes. The authors apply the method to a large scale problem in which there are 61 waypoints and about 7000 nodes, and actual topological information and recorded weather information are used as obstacles. The simulation result shows the method can be used in real time.
著者
神永 晋 富岡 定毅 山岬 裕之
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.53, no.623, pp.554-561, 2005 (Released:2006-01-06)
参考文献数
16
被引用文献数
1

Flow behavior and thrust performance of MHD energy bypass scramjet engine was examined numerically. MHD generator was placed at the isolator to enhance the flow compression. Kinetic energy was converted to electrical energy in the MHD generator. Extracted electrical energy was consumed at the MHD accelerator placed at the downstream of the combustor. When MHD energy bypass system was used, the flow was decelerated and compressed in the MHD generator. Effect of velocity and Mach number on wall friction was analyzed and decrease of friction force was pointed out. Also, high pressure in the combustor resulted in increase of pressure contribution to net thrust. Despite of positive effects, decelerating Lorentz force in the MHD generator was comparably large and no significant difference in net thrust performance is observed.