著者
東 大輔 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 (ISSN:13446460)
巻号頁・発行日
vol.51, no.589, pp.52-60, 2003 (Released:2003-09-16)
参考文献数
17
被引用文献数
3 3

The subsonic flow for a 45 deg-swept delta wing was numerically simulated to see the effects of rotational leading edges on aerodynamic forces. In the present study, part of the cylindrical leading edge can be rotated which extends from x=0.25C to 0.90 C. The computation has been performed at an angle of attack of 20 deg and a Reynolds number of 2.0×104 based on the maximum wing root chord. Under these conditions, the flow is fully separated from the wing surface in the case without leading edge rotation, so that no suction peaks due to leading edge vortices appear over the upper surface of the wing. Consequently, the delta wing will not have an effective vortical lift. In the case of steady rotation, leading edge vortices were produced on the wing in the early stage. However, a gradual drop in lift coefficient occurred as a result of the diffusion of these vortices. By contrast, in the case of unsteady rotation, a pair of leading edge vortices was maintained, so that a higher lift was produced. Consequently, the lift coefficient became more than 40% higher than that of the plain delta wing.
著者
小紫 公也 中川 樹生 大村 俊介 荒川 義博
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.624, pp.18-22, 2006 (Released:2006-02-20)
参考文献数
15

Main-lobe energy transmission using an optical phased array is proposed. Effects of spatial and temporal coherence of rectangular-symmetric laser arrays on energy transmission performance are evaluated in terms of the main-lobe beam quality factor and the main-lobe energy transmission efficiency. As a result, the efficiency is found independent of the number of laser elements and their spectral broadening, and sensitive to the aperture fill factor. The main-lobe beam quality factor remains constant for any cases.
著者
上野 陽亮 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 (ISSN:13446460)
巻号頁・発行日
vol.57, no.667, pp.317-322, 2009 (Released:2009-08-17)
参考文献数
13
被引用文献数
2 1

A numerical simulation method taking into account both aerodynamics and flight dynamics has been developed to simulate the flight of a low speed flying object, where it undergoes unsteady deformation. This method can also be applied to simulate the unsteady motion of small vehicles such as micro air vehicles (MAV). In the present study, we take up a bird and demonstrate its flight in the air. In particular the effect of fluid forces on the bird's flying motion is examined in detail, based on CFD×CFD: Computational Fluid Dynamics (CFD) and Computational Flight Dynamics. It is found from simulated results that this bird can generate lift and thrust enough to fly by flapping its wing. In addition, it can make a level flight by adjusting its oscillation frequency. Thus, the present method is promising to study the aerodynamics and flight dynamics of a moving object with its shape morphing.
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 (ISSN:13446460)
巻号頁・発行日
vol.50, no.578, pp.95, 2002 (Released:2003-08-19)
参考文献数
9
被引用文献数
7 6

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.
著者
大南 香織 小川 博之 林 光一
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.1-10, 2008 (Released:2008-03-11)
参考文献数
10
被引用文献数
1 1

Hydrazine (N2H4) and NTO (dinitrogen tetroxide: N2O4) mixtures are used in spacecraft bipropellant systems, having the advantage, for sampling missions, of having no carbon composition. However, no reasonable hydrazine and NTO combustion model has been developed. To construct a hydrazine and NTO combustion model that is useful for bipropellant thruster CFD simulation, we extracted efficient elementary reactions from detailed kinetic reaction model proposed by Ohminami and Ogawa in 2007. The reduced hydrazine and NTO combustion model was composed of 61 extracted reactions with 23 chemical species and was coincident with the original detailed kinetic reaction model in terms of combustion gas temperatures and ignition delay times over O/F(oxidizer and fuel mass ration) =0.82-1.84. Also the simulated combustion gas temperatures were good agreed with the adiabatic flame temperatures, and the simulated ignition delay time at O/F=1.2 was consistent with the literature value. Chemical reaction paths before and after ignition were showed, and could explain hydrazine and NTO combustion network mechanism change.
著者
水野 洋
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.55, no.638, pp.55-59, 2007-03-05 (Released:2019-04-22)
参考文献数
8
著者
水野 貴秀 福田 盛介 坂井 智彦 岡田 祐 有井 基文 西村 健志 入部 紘一 長谷川 秀樹 片山 翔太 遠藤 勉 辻 雅生
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
pp.JSASS-D-17-00008, (Released:2017-08-03)

The landing radar employs a pulse-type radar using 4.3 GHz C-band microwave radiation. It has a wide beam for measuring the altitude in vertical direction, as well as four narrow tilted beams for measuring the velocity in horizontal direction. In this paper, development of the Bread Board Model (BBM), a field experiment, and the design of SLIM loading Flight Model (FM) are introduced. Furthermore, the radar simulator required for FM development of a radar is explained.
著者
小林 修
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.49, no.575, pp.419-424, 2001 (Released:2002-04-26)
参考文献数
10

This paper discusses a static stability theory for airplanes. The conventional definitions of static stability are neither clear nor systematic. On the basis of these situations, in the first report of this paper, a system of definitions on 6 static stability concepts was proposed, and two concepts of static flight-velocity stability and static angle of attack stability were studied. And in the second report, a concept of static pitch stability was discussed. This third report discusses on the three static stability concepts in sideslip, roll and yaw, and proposes that “dY/dβ<0, ” “dR/dΦ<0” and “dN/dΨ<0” should be used as the fundamental definitions, where R means rolling moment. The general criteria for these static stabilities are deduced from these definitions. From these criteria, “CYβ<0, ” “Clβ/CYβ>0” and “Cnβ>0” are obtained as the stable conditions. Finally, this report represents the whole summary of this paper.
著者
浅川 純 小泉 宏之 西井 啓太 服部 旭大
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.10, pp.296-301, 2018-10-05 (Released:2018-10-05)
参考文献数
21

超小型深宇宙探査機EQUULEUSは,2020年にNASAのSLSによって,メインペイロードである無人宇宙船Orionの副ペイロードとして打ち上げ予定のキューブサットである.EQUULEUSのミッションの一つが太陽-地球-月系における軌道操作技術の実証である.その核となる技術が小型水レジストジェットスラスタAQUARIUSである.AQUARIUSには,軌道遷移と姿勢制御の2種類の推進性能が要求される.水を推進剤として共有利用することで,2種類の推進性能を確保しつつ,高圧ガスシステムから脱却した小型推進系が実現される.また,安全無毒で取扱い性が良い水は,相乗り打ち上げされることが多い小型宇宙機との親和性が高い.AQUARIUSのエンジニアリングモデルを開発し,探査機構体に組み込んだ状態で性能評価試験及び環境試験を実施した.小型宇宙機という特徴を生かし,探査機を丸ごと用いて推進系の作動試験を実施することで,電源系や熱系等も考慮しつつ,推進性能を統合的に評価した.本稿では,AQUARIUSエンジニアリングモデルの開発状況について概観する.
著者
野田 譲 小林 修
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.633, pp.467-475, 2006 (Released:2006-11-20)
参考文献数
2

Most airplanes use their ailerons to compensate the lateral displacement deviation from a reference flight-path. This study proposes a method of lateral flight-path control due to the rudder steering under constraint of automatic roll angle hold. This control method is estimated analytically to produce quicker lateral displacement response than the control due to aileron. Then, experiments using a flight simulator are carried out to evaluate the control characteristics on the task of holding the flight path. The pilot’s evaluation results show that, the rudder steering method gives better flying qualities than aileron steering method. Furthermore, as the more practical control measures, the mixture type of method is worked out, which is transferred from aileron steering to rudder steering depending on the lateral displacement deviation from a reference flight-path.