著者
山井 洋一 本田 健一郎
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.71, no.4, pp.192-202, 2023 (Released:2023-08-05)
参考文献数
30

This paper proposes the evaluation methodology in early design phase for the feasibility of novel instrument layout to be applied for the next generation civil aircraft, based on the MIL-HDBK-46855A human engineering guideline that shows pilot evaluation and analysis method for military system. Airline pilots evaluation on mockup with this method facilitates to identify the critical design issue and its potential resolutions from visibility, its trajectory and crew coordination point of view and mitigate the risk for late finding of issue to avoid redesign in later design phase. The effectiveness of the evaluation method is potentially shown by the trial usage on the conventional instrument layout, and the achieved data can be used for a reference to compare it with the novel instrument layout design.
著者
本田 俊樹 山極 芳樹
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.50, no.579, pp.150, 2002 (Released:2003-08-19)
参考文献数
9
被引用文献数
1 1

This paper reports results of an improved model of “ionospheric hole” caused by rocket exhaust injected into the F-region. We have investigated a practical “ionospheric hole” model by which a proper strategy of rocket launch can be examined from a view point of protection of the Earth’s environment. The analytical results of preceding models were published about 8 years ago. The model well included the trajectory of launch rocket and could evaluate the effect of rocket exhaust on the Earth’s environment for various trajectories. The analytical results, however, didn’t quantitatively agree with the observation data very well. The new model includes the effects of the exhaust velocity of effluents and the neutral wind that preceding model didn’t take into account, and the boundary conditions and parameters are improved. The analytical results by this improved model well agree with the observation data for Skylab–I and HEAO–C launching experiments not only qualitatively but also quantitatively.
著者
伊勢 俊之 月崎 竜童 都甲 浩芳 小泉 宏之 國中 均
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.62, no.6, pp.212-218, 2014 (Released:2015-08-20)
参考文献数
12

The microwave ion thruster μ10's ion beam current saturated at a large mass flow rate when propellant gas was injected from a waveguide inlet and it was improved by additional propellant inlets to a discharge chamber. In order to understand the mechanism of these phenomena, it is important to measure distributions of the microwave electric field inside the discharge chamber, which is directly related to plasma production. In this study, we applied an electro-optic (EO) probe to measuring the microwave electric field. The probe contains no metal and can be accessed in the discharge chamber with less disruption to the microwave distribution. We measured electric-field profiles along the centerline and in the ECR area of μ10 with the EO probe. Consequently, this paper revealed that when the propellant was injected from the waveguide inlet, microwave was reflected in the waveguide at large mass flow rate, which disturbed a propagation of microwave to the ECR area. It also revealed that when the propellant was injected from the discharge chamber inlet, the mass flow rate where the microwave reflection occurred shifted to larger rate, which resulted in the increase of the beam current.
著者
東野 和幸 杉岡 正敏 小林 隆夫 湊 亮二郎 丸 祐介 笹山 容資 大塚 雅也 牧野 隆 坂口 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.57, no.664, pp.210-216, 2009 (Released:2009-06-01)
参考文献数
10
被引用文献数
3 2

Liquid Natural Gas (LNG) will be used as propellant of near future space vehicles and rocket engines. Cooling characteristics of engines, especially methane thermal cracking characteristics depend on material candidate for nozzle and chamber cooling passage material temperature. This paper describes these effects on coking and sample analysis method is suggested.
著者
奥村 哲平 増井 博一 豊田 和弘 趙孟 佑 今泉 充
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.647, pp.590-596, 2007 (Released:2007-12-27)
参考文献数
14
被引用文献数
6 7

Electrostatic discharge (ESD) occurs on the solar array due to space plasma interaction. It is considered that solar cell suffers degradation of electric performance, once ESD occurs at the solar cell edge. In order to study the degradation of solar cell electrical performance, we performed ESD tests on Si solar cell in a vacuum chamber. After the ESD tests the solar cell maximum power decreased. We found the damage on surface electrode in the vicinity of ESD spot. Infrared emission due to current leak was found at the spot. The solar cell degraded due to the leak resistance produced by ESD.
著者
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.52, no.610, pp.514-521, 2004 (Released:2005-01-05)
参考文献数
11
被引用文献数
9 13

The air breathing ion engine (ABIE) is a new type of electric propulsion system which can be used to compensate the aerodynamic drag of the satellite orbiting at extremely low altitudes. In this propulsion system, the low-density atmosphere surrounding the satellite is taken in and used as the propellant of ion engines to reduce the propellant mass for a long operation lifetime. Since feasibility and performance of the ABIE are subject to the compression ratio and the air intake efficiency, a numerical analysis has been conducted by means of the direct-simulation Monte-Carlo method to clarify the characteristics of the air-intake performance in highly rarefied flows. Influences of the flight altitude, the aspect-ratio of the air intake duct, the angle of attack, and the wall conditions are investigated.
著者
佐藤 昌之 村岡 浩治 穂積 弘毅 眞田 幸尚 山田 勉 鳥居 建男
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.65, no.2, pp.54-63, 2017 (Released:2017-04-05)
参考文献数
10
被引用文献数
1 1

This paper is concerned with the design problem of preview altitude controller for Unmanned Airplane for Radiation Monitoring System\nobreakspace {}(UARMS) to improve its control performance. UARMS has been developed for radiation monitoring around Fukushima Dai-ichi nuclear power plant which spread radiation contaminant due to the huge tsunamis caused by the Great East Japan Earthquake. The monitoring area contains flat as well as mountain areas. The basic flight controller has been confirmed to have satisfactory performance with respect to altitude holding; however, the control performance for variable altitude commands is not sufficient for practical use in mountain areas. We therefore design preview altitude controller with only proportional gains by considering the practicality and the strong requirement of safety for UARMS. Control performance of the designed preview controller was evaluated by flight tests conducted around Fukushima Sky Park.
著者
平野 正隆 宮路 幸二
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.611, pp.535-540, 2004 (Released:2005-02-25)
参考文献数
8
被引用文献数
1 1

A wing rock is known to be a self-excited rolling oscillation of a delta wing that is induced by unsteady aerodynamic forces. In this study, free-to-roll simulations are carried out by incorporating time-accurate computational fluid dynamics with an equation of motion of a wing. A limit cycle oscillation and the histogram of a hysteresis in the rolling moment, which has four peaks within one cycle, are successfully simulated. The strength of the leading-edge vortices at a fixed roll angle is rather different from that during the wing rock especially at large angular velocities and that causes the characteristics behavior of the unsteady moments.
著者
岡林 希依 末永 宇識 淺井 雅人
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 (ISSN:13446460)
巻号頁・発行日
vol.64, no.1, pp.41-49, 2016 (Released:2016-02-05)
参考文献数
28
被引用文献数
2

For practical CFD-aided design of riblets on aircrafts, we are aiming to develop a Reynolds-Averaged Navier-Stokes (RANS) turbulence model which can simulate drag reduction effects without resolving fine-scale flows near the riblets. Wilcox's rough wall boundary condition for Menter's SST model is modified to reproduce velocity shift in logarithmic region corresponding to riblet's drag reduction effects. Two basic relations for this model are derived from available experimental data and parametric analysis, and are validated in zero-pressure gradient boundary layers with two different-geometry riblets. Drag reduction rates corresponding to experimental results can be obtained with these relations. The new model, however, underestimates the effects of riblet mounted on NACA0012, which suggests that further improvement of the model is needed to account for influences of pressure gradient.
著者
溝口 誠 山口 裕
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.60, no.3, pp.121-127, 2012 (Released:2012-10-23)
参考文献数
15
被引用文献数
2 3

The effect of aspect ratio (AR) on the aerodynamic characteristics of rectangular wings is investigated. Reynolds numbers considered are 7.6×104 and 5.2×104. Experimental results are compared with analytical ones obtained from Lamar's method. It is shown that the aspect ratio of wings affects the stall characteristics when AR≤2.0. The aspect ratio also has an effect on the lift slope if AR≤1.5. Furthermore, maximum lift coefficients increase when AR≤1.0. Comparisons show that the variations of aerodynamic characteristics are caused by tip vortices. It is also considered that the position of the center of pressure is varied with the angle of attack because of the effects of the laminar separation bubble and tip vortices on wing surfaces.
著者
榊 和樹 舩橋 友和 中谷 辰爾 津江 光洋 金井 竜一朗 鈴木 恭兵 稲川 貴大 平岩 徹夫
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.65, no.5, pp.193-199, 2017

The longitudinal combustion instability characteristics of a pintle-type injector for a bipropellant rocket engine combustor are investigated experimentally. An optically accessible combustion chamber are used to observe unsteady combustion behaviors under oscillating combustion conditions. CH* chemiluminescence and backlit spray images are observed simultaneously with two high-speed cameras. Two experiments with the propellant total momentum ratio (TMR) of 0.76 and 2.48 are conducted, whereas the combustion pressure and the propellant mixture ratio are 0.45 and 1.6, respectively. The combustion oscillations at the natural frequencies of the chamber longitudinal acoustic mode are observed when the TMR is 0.76. The combustion oscillation is caused by the coupling between the heat release and the combustion chamber acoustics. When the TMR is 2.48, the combustion oscillations at the frequencies of 400 and 800Hz, which are lower than the first longitudinal mode frequency, are observed. Since the 400Hz corresponds to the convective time scale in the combustion chamber, the oscillations could be caused by one of the convective modes such as entropy wave.
著者
角銅 洋実 榊 和樹 中谷 辰爾 津江 光洋 金井 竜一郎 稲川 貴大 平岩 徹夫
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.65, no.1, pp.1-9, 2017

The pintle injector is a promising candidate for injection systems of future rocket engines because of the throttling capability, the combustion stability, and the low manufacturing cost. Few studies focusing on fundamental aspects of a pintle injector have been conducted, and most of the design parameters of a pintle injector is determined mainly based on the empirical knowledge. Among the design parameters, total momentum ratio (TMR) is one of the most important parameters since spray structure is dominated by TMR. Therefore, combustion experiments using an ethanol/liquid oxygen rocket engine combustor with a planar pintle-type injector which is designed for optical measurements for a pintle injector are conducted at combustion pressure (<I>P<sub>c</sub></I>) = 0.37-0.42MPa, mixture ratio (O/F) = 1.31-1.49, TMR = 0.32-3.65 to investigate the effects of propellant momentum ratio on the combustion behavior. The spray structure under hot fire conditions is observed using high-speed imaging techniques with a backlit configuration. In the oxidizer-centered configuration, the characteristic exhaust velocity efficiency (<I>η<SUB>C</SUB><SUP>*</SUP></I>) decreases with the increase of the TMR. The atomized propellant impinge on the combustor wall before the vaporization and reaction at higher TMR. In the fuel-centered configuration, though the propellant spray is more inclined to the direction of the upper combustor wall at higher TMR, the <I>η<SUB>C</SUB><SUP>*</SUP></I> does not change with the TMR. In both oxidizer-centered and fuel-centered, higher <I>η<SUB>C</SUB><SUP>*</SUP></I> is provided in the condition of higher injection pressure drop.
著者
原田 正志
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.66, no.3, pp.75-83, 2018 (Released:2018-06-05)
参考文献数
10

In this paper, a design method to obtain the maximum static thrust ducted fan is proposed. In this method, the shape of the optimum blade is obtained by minimizing the objective function. The objective function includes the effect of the leading edge suction that acts on the duct's rip. The shape of the optimum blade is tapered, however, a small expansion is confirmed at blade tip. The amount of this expansion depends on the radius of duct's rip. From the optimized ducted fan, it is concluded that the duct generates nearly half of the total thrust, which is also predicted by the simple momentum theory.
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
五井 龍彦 田中 裕久 中島 健一 渡辺 浩二
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.678, pp.203-209, 2010 (Released:2010-07-26)
参考文献数
6
被引用文献数
4 3

A half-toroidal traction drive CVT has a feature of small spin at traction pitch in whole speed ratio range of 1:4, which suits to transmit high rotational speed with minimum temperature increase of traction surface. Research activity on traction drive CVT has commenced in 1996 for applying it to an aircraft 24,000rpm constant-speed generator instead of a hydro-static transmission. This paper shows fundamental design of 90kW traction drive integrated drive generator, ``T-IDG", and stability analysis on a sensor-less electro-hydraulic speed control servo-mechanism by bond graphs. The performance test of T-IDG mounted on a test bench and an actual jet engine proved that the control system using sensor-less servomechanism can keep the generator speed within MIL-STD-704E allowable limit against steep changes of speed and load.
著者
永田 靖典 山田 和彦 鈴木 宏二郎 今村 宰
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.1, pp.1-8, 2019 (Released:2019-02-05)
参考文献数
13
被引用文献数
1

The satellite communication system without ground antennas is highly beneficial to ease construction and maintenance of the ground station. To realize it, the Iridium communication service which is consisted of 66 satellites on the LEO (Low-Earth Orbit) is focused. The telemeter and command data are transmitted and received through the Internet, Iridium ground station, and Iridium satellites. Then, only a PC connecting to the Internet is required for the present telecommunication system. To demonstrate this concept, the EGG (re-Entry satellite with Gossamer aeroshell and GPS/iridium) nanosatellite mission was conducted in 2017, which is the first satellite operated via only the Iridium SBD (Short Burst Data) communication. In this paper, the communication performance of the Iridium communication applied to LEO satellite is investigated and the EGG mission result is described. Trajectory-based simulation shows that the present system will function well even under the Doppler shift criteria, though the available time rate will be degraded. Actually, it worked successfully on the EGG mission regardless of the satellite location. Moreover, the telemeter data was acquired in semi-real time manner on the atmospheric-entry phase, which is very difficult for the ordinary ground antenna system. This should be the important feature of the present system.
著者
西川 雅章 逸見 啓 パク サンチョル 灘部 岳晃 武田 展雄
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 (ISSN:13446460)
巻号頁・発行日
vol.58, no.680, pp.261-268, 2010 (Released:2010-09-27)
参考文献数
15
被引用文献数
1 1

Carbon fiber-reinforced composites have been recently applied for engine fan blades, because of their high specific strength. In the design of the fan blade, the bird-strike impact is one of the greatest concerns, since impact-induced damage can lead to the engine stall. This study presented a numerical method to analyze the bird-strike impact as a soft-body impact on cantilevered composite panel. Especially, we coupled a stabilized dynamic contact analysis, which enables predicting impact force on the panel appropriately, with laminate damage analysis to predict the impact-induced progressive damage in the composite. This method was verified through the comparison with the experimental results. With the numerical method, we investigated the effect of impact condition, blade thickness and shape on the impact-induced damage in composite fan blade subjected to a bird strike. An intermediate blade thickness and a large blade curvature help improving the bird-striking impact resistance of the composite.
著者
歌島 昌由 川口 淳一郎
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.50, no.580, pp.210, 2002 (Released:2003-09-02)
参考文献数
3
被引用文献数
1 2

The stability of the orbits around the sphere of influence of the secondary body in the circular restricted three-body problem is discussed. This orbit is called “Pseudo Orbit” here. Though there exists a stability limit for the inclination of the pseudo orbit, the whole story of the instability was not resolved. In this paper, it is shown at first that the out-of-plane motion of the pseudo orbit causes disturbances in the in-plane motion by the method of virtual energy. Then, it is shown that the disturbances are governed by the Mathieu’s equation which has the periodic coefficient, and the rigorous mathematical property of the instability of the pseudo orbit is presented.
著者
畑井 啓吾 池田 博英
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.5, pp.174-180, 2019 (Released:2019-10-05)
参考文献数
32

The suitable fuel for reduced-toxicity hypergolic bipropellant has been explored in this study. High concentration of hydrogen peroxide and sodium borohydride were used as an oxidizer and a fuel additive for ignition source. Fuel candidates were narrowed down by many requirements such as toxicity, chemical regulation, storability, cost, specific impulse, solubility of additive and ignition delay. As a result, 3-methylaminopropylamine (MAPA) was selected as the best fuel for reduced-toxicity bipropellant. MAPA doped with sodium borohydride showed very fast hypergolicity with hydrogen peroxide and its ignition delay time was less than 10msec. MAPA and hydrogen peroxide bipropellant can achieve 98.3% of theoretical specific impulse of MMH/NTO, whereas MAPA has low toxicity compared with MMH.
著者
河内 俊憲 三谷 徹 平岩 徹夫 富岡 定毅 升谷 五郎
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.51, no.595, pp.403-411, 2003 (Released:2003-09-26)
参考文献数
15
被引用文献数
2 6

A one-dimensional theoretical method for an evaluation of the net thrust of a scramjet engine is presented. To calculate the thrust performance of the engine analytically, an efficiency characterizing compression process, such as recovery factor in total pressure or kinetic energy efficiency etc., is necessary. In the previous theoretical method, this efficiency was roughly assumed. Although the effect of aerodynamic parameters and configuration parameters on the thrust can be investigated with this rough assumption, the net thrust evaluated with this method was not enough accurate to be compared with the measured thrust in experiments. The total pressure loss is chosen as the efficiency in this paper. This total pressure loss is evaluated from the engine internal drag with the wind tunnel experiment, which is due to irreversible process through the engines. The theoretical maximum thrust of the engines can be calculated with this new method.