著者
吉川 俊明 坂本 慎介 堀 琴乃 楠本 寛 山本 康 服部 高資 佐多 宏太
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.56, no.655, pp.391-395, 2008-08-05
参考文献数
7
被引用文献数
1 1

In this paper, we propose the method for the measurement of required power and the adjustment of optimum gear ratio in take-off ground running. To get the values of required power and speed, we measured torque of the left side and the right side of pedals, RPM of pedals, and speed of the cockpit frame. In order to improve the take-off speed, some drums were applied, and the optimum gear ratio of the front drum to the rear drum was determined.
著者
山口 敬之 松岡 健 八桁 純 笠原 次郎
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 = Journal of the Japan Society for Aeronautical and Space Sciences (ISSN:13446460)
巻号頁・発行日
vol.57, no.663, pp.141-147, 2009-04-05
参考文献数
22
被引用文献数
2

In the present study, a dynamics model of an inflow-drive valve for pulse detonation engines (PDEs) is proposed, in which system the inflow of the valve periodically drives the valve piston. Since the inflow-drive valve needs no energy source to drive the piston, the mass flow rate divided by the valve mass is relatively large, and the response time for the mass-flow-rate change can be short. Moreover, the inflow-state condition for the stable valve operation is not restricted. The two-cylinder three-fluid type inflow-drive valve was fabricated. The maximum mass flow rate for one valve was evaluated as 6.3g/s, in which system the mass of the piston, the spring constant, and the supplied pressure were 3.8kg, 9800N, and 1.0MPa, respectively. The total mass flow rate using propellant was evaluated as 12g/s. The PDE system was constructed by using these inflow-drive valves. This system was stably operated in the frequency of 17.52Hz.
著者
山本 悟 葉狩 秀樹 村山 光宏
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.47, no.540, pp.41-46, 1999-01-05
参考文献数
10
被引用文献数
1

The nonequilibrium condensation generating around the 2-D and 3-D wings in moist air, so-called 'Vapor Trail, ' is numerically investigated. The fundamental equations composed of the compressible Navier-Stokes equations and tho model equations for the phase change based on the classical condensation theory are solved using the fourth-order accurate compact MUSCL TVD scheme and the second-order Runge-Kutta scheme. As numerical examples, the 2-D transonic viscous flows around the RAE 2822 wing in moist air are calculated changing the relative humidity and the calculated results are compared with those in dry air and the experiment. Also the 3-D flows around the ONERA M 6 wing in moist air are preliminary calculated.
著者
田原 弘一 弓削 政郎 白崎 篤司 マルチネスサンチェス マヌエル
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.52, no.608, pp.408-415, 2004-09-05
被引用文献数
4 2

Low-power Hall thruster flowfields were calculated using a simple one-dimensional model to understand plasma characteristics and ion acceleration processes and to predict thruster performance. The influences of magnetic field strength and acceleration channel length were mainly examined. The thruster model for calculation is the THT-IV low power thruster developed in Osaka University. Generally, ions were produced in an upstream region from the anode to some axial location of the acceleration channel, and then they were intensively accelerated in a region downstream just from the ionization region. With too short channel, ionization began downstream just from the anode, and then ion acceleration also occurred in the same region, resulting in poor ion flux and low thrust performance. In large channel length, the channel was long enough to produce a fully-ionized plasma, and efficient ion production and acceleration occurred. When the magnetic field strength increased in the channel, ionization occurred in a more upstream region, and ion acceleration began in the same region; that is, ionization and acceleration overlapped in the relatively long region. On the other hand, with a weak magnetic field ion production and acceleration, intensively and efficiently, occurred in their thin regions. Furthermore, we tried to include unclear anomalous electron diffusions by changing a Bohm diffusion coefficient at each high magnetic field strength in order to fit a calculated performance to the measured one. The calculated discharge current almost equaled the measured one, and the thrust characteristic also agreed well with the measured one.
著者
前川 昭二 斉藤 勝也
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.51, no.595, pp.412-418, 2003-08-05
参考文献数
8

An airship has usually two or three ballonets in its envelope in which air is contained. Its buoyancy and attitude control is performed by changing the air content of each ballonet. It is said that ballonet slosh may influence airship's stability or ride quality. However, no quantitative treatment has been performed so far to investigate this phenomenon. In this paper the coupled equations of an airship longitudinal motion are formulated by modeling the ballonets as cylindrical containers. Some numerical calculations are performed for a 25m class airship and it has been shown that the ballonet slosh may become a design issue when the shape of the ballonet is thinner or when the size becomes larger.
著者
水野 貴秀 津野 克彦 奥村 英輔 中山 通雄
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.54, no.634, pp.514-521, 2006-11-05
被引用文献数
2 1

Hayabusa, launched May 2003, is the first Japanese spacecraft to explore the small asteroid Itokawa (1998SF36) and touched down on Itokawa twice to sample of the surface material. LIDAR (LIght Detection And Ranging) is an important navigation sensor for the asteroid explorer to measure distance between the spacecraft and the asteroid. Since it is carried in a planetary exploration spacecraft, the weight of LIDAR is very lightweight of 3.7kg. In the rendezvous and touchdown operation, LIDAR supplied the ranging data to the spacecraft navigation system to approach Itokawa down to 50m and its total shots number of laser pulse was more than 4 million. The composition and basic performance of LIDAR are explained and this paper also reports the ranging data at the time of landing to asteroid Itokawa of the autumn of 2005.
著者
城武 雅 郭 東潤 李家 賢一 砂田 保人
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.54, no.627, pp.175-180, 2006-04-05
参考文献数
10
被引用文献数
1 1

Wind tunnel tests were conducted to investigate static roll characteristics of an SST model at high angles of attack. The Reynolds number based on the mean aerodynamic chord was 6.2&times;10<SUP>4</SUP>. Normal force and rolling moment measurements have been done at different roll angles for the cranked arrow wing SST model. Smoke visualizations and Particle Image Velocimetry (PIV) measurements were also performed. Force measurement results were compared both with flow visualization pictures and with PIV measurement results. It was shown that the vortex breakdown has strong influences on the static roll characteristics of the cranked arrow wing.
著者
香山 寛人 汪 運鵬 小澤 啓伺 土井 克則 中村 佳朗
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.60, no.2, pp.74-79, 2012-04-05
参考文献数
12
被引用文献数
1

The space transportation system will need advanced abort systems to secure crew against serious accidents. Here this study deals with the capsule-type space transportation systems with a Launch Abort System (LAS). This system is composed of a conic capsule as a Launch Abort Vehicle (LAV) and a cylindrical rocket as a Service Module (SM), and the capsule is moved away from the rocket by supersonic aerodynamic interactions in an emergency. We propose a method to improve the performance of the LAV by installing fences at the edges of surfaces on the rocket and capsule sides. Their effects were investigated by experimental measurements and numerical simulations. Experimental results show that the fences on the rocket and capsule surfaces increase the aerodynamic thrust force on the capsule by 70% in a certain clearance between the capsule and rocket. Computational results show the detailed flow fields where the centripetal flow near the surface on the rocket side is induced by the fence on the rocket side and the centrifugal flow near the surface on the capsule side is blocked by the fence on the capsule side. These results can confirm favorable effects of the fences on the performance of the LAS.
著者
土井 克則 Mohd FADHLI 川島 渉 中村 佳朗
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.59, no.693, pp.273-280, 2011-10-05
参考文献数
14
被引用文献数
3

A boomerang thrown properly into the air can fly in an elliptical path and return to the point of origin. In this study, such a motion of the boomerang was numerically simulated to clarify the mechanism of the motion. The simulation was conducted by the double CFD method which is the coupling method of the computational fluid dynamics and the computational flight dynamics. We considered the case that a small flat boomerang was thrown with a translational and a rotational velocity, an angle of the translational velocity from a horizontal plane, and no roll angle. Results showed that the boomerang lifted and traveled in a path with changing roll and pitch angles due to a pressure distribution on its surface, and returned to a point near the origin. Furthermore, an experiment was performed to confirm the validity of the computational results, and the experimental result was qualitatively corresponding to the computational results.
著者
國中 均 西山 和孝 清水 幸夫 都木 恭一郎 川口 淳一郎 上杉 邦憲
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.52, no.602, pp.129-134, 2004-03-05
被引用文献数
4 6

The microwave discharge ion engine generates plasmas of the main ion source as well as the neutralizer using 4GHz microwave without discharge electrodes and hollow cathodes, so that long life and durability against oxygen and air are expected. MUSES-C "HAYABUSA" spacecraft installing four microwave discharge ion engines was launched into deep space by M-V rocket on May 9, 2003. After vacuum exposure and several runs of baking for reduction of residual gas the ion engine system established the continuous acceleration of the spacecraft toward an asteroid. The Doppler shift measurement of the communication microwave revealed the performance of ion engines, which is 8mN thrust force for a single unit with 3,200sec specific impulse at 23mN/kW thrust power ratio. At the beginning of December 2003 the accumulated operational time exceeded 7,000 hours and units.
著者
今度 史昭 平家 祐貴 木下 拓也
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.670, pp.437-444, 2009-11-05
参考文献数
4

A new point mass model of the air vehicle has been developed in our laboratory. This model employs angle-of-attack, side slip angle, bank angle and thrust, as four control variables. The existent three control variables point mass model cannot introduce the winds and active side slip angle control, while this new model can introduce them. This paper explains about the model at first. The model is applied to the YF-16 aircraft and simulations are conducted for two maneuvers as typical examples, which show the effectiveness and the preciseness of this model.
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
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 = Journal of the Japan Society for Aeronautical and Space Sciences (ISSN:13446460)
巻号頁・発行日
vol.54, no.635, pp.542-548, 2006-12-05
被引用文献数
9 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
山根 秀公 松永 易 草川 剛
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.56, no.649, pp.80-87, 2008-02-05
被引用文献数
1 1

A flyable FADEC system engineering model incorporating Integrated Flight and Propulsion Control (IFPC) concept is developed for a highly maneuverable aircraft and a fighter-class engine. An overview of the FADEC system and functional assignments for its components such as the Engine Control Unit (ECU) and the Integrated Control Unit (ICU) are described. Overall system reliability analysis, convex analysis and multivariable controller design for the engine, fault detection/redundancy management, and response characteristics of a fuel system are addressed. The engine control performance of the FADEC is demonstrated by hardware-in-the-loop simulation for fast acceleration and thrust transient characteristics.
著者
秋葉 鐐二郎 青木 嘉範 加勇田 清勇 藤井 篤之 永田 晴紀 佐鳥 新
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.51, no.591, pp.141-150, 2003-04-05
参考文献数
11
被引用文献数
1 2

The staged combustion hybrid rocket is under development by our research group since 1999. This hybrid rocket engine consists of two combustion chambers. The primary combustion chamber is the fuel tank itself filled with granular solid fuels. The fuel rich gas generated by the first stage combustion flows into the secondary combustion chamber, which is located in the bottom of the primary combustion chamber. The additional oxidizer is injected to the secondary combustion chamber in order to attain an optimal specific impulse by completing combustion. There are two types of the primary combustion. One is nicknamed as the incinerator type; the other is called the multi-grain type. This new type engine is featured with a wide range throttling capability and an extensive freedom in selecting the fuel material. This paper deals with the incinerator type. Presented are preliminary experiments as well as the systems description.
著者
大屋 裕二 烏谷 隆 桜井 晃
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.50, no.587, pp.477-482, 2002-12-05
被引用文献数
6 13

We have developed a new wind turbine system that consists of a diffuser with a broad-ring brim at the exit periphery and a conventional wind turbine inside it. The new wind turbine has demonstrated power augmentation for a given turbine diameter and wind speed by a factor of about 2–3 compared with a bare wind turbine. This is because a very low-pressure region due to strong vortex formation behind the broad brim draws more mass flow to a turbine inside the diffuser.
著者
松井 信 小紫 公也 Georg Herdrich Monika Auweter-Kurtz
出版者
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.53, no.619, pp.379-384, 2005-08-05
被引用文献数
3 1

Absorption spectroscopy has been applied to the measurement of the arc-heater plumes. Number density distributions of atomic metastable oxygen were obtained from the measured absorption line profile at 777.19 nm in argon-oxygen plumes generated by arcjet type arc-heaters. As a result, it was found that the oxygen is localized off axis at the nozzle exit, and diffuses from outside toward the centerline in the plume. Moreover, numerical simulation was conducted to investigate the diffusion process of the oxygen in the arc-heater. The result indicates that the maximum degree of oxygen dissociation would be at the level of 0.01%.
著者
河野 功 杢野 正明 鈴木 孝 小山 浩 功刀 信
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.50, no.578, pp.95-102, 2002-03-05
被引用文献数
12 7

ETS–VII is a test satellite to perform in-orbit demonstration of autonomous rendezvous docking (RVD) technology, which will be necessary for advanced space activities in the early 21st century. ETS–VII performed three RVD experiment flights, and verified all technical items. ETS–VII demonstrated first autonomous RVD between unmanned vehicles, and remote piloted rendezvous flight position accuracy at docking was about 1cm, and acceleration was less than 1.5mG (low impact docking). In the second RVD experiment flight, ETS–VII detected attitude anomaly and executed disable abort for safety insurance. We present the results and evaluation of three RVD experiment flights in this paper.