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航空宇宙技術研究所 7-9 Jun. 2000 東京 日本, National Aerospace Laboratory 7-9 Jun. 2000 Tokyo Japan, 航空数値シミュレーションに関する、以下の主題を論じている。計算流体力学、超音速旅客機および宇宙往還機開発、航空用エンジンシミュレーション、計算機開発、数値風洞、航空機性能評価システム、翼型失速、熱空力環境、遷音速流解析、空力設計、ノズル流れ、回転曲管内流、流れの可視化、フラップ歪み、乱流解析、離陸時特性、空力弾性解析、翼端漏れ渦崩壊、翼後流相互作用、超音速パルスジェット衝突、混合促進、および境界層厚。, The following topics on aerospace numerical simulation were discussed: computational fluid dynamics, development of super sonic transports, reusable space transportation systems, aero-engine simulation, computer development, numerical wind tunnels, the computational aerodynamics system for performance evaluation and research, airfoil stall, aerothermodynamic environments, transonic flow analysis, aerodynamic design, nozzle flow, fluid flow in rotating heated curve pipes, flow visualization, flap distortion, turbulence analysis, take-off characteristics, aeroelasticity analysis, tip leakage vortex breakdown, blade wake interaction, supersonic pulse jets impinging, mixing enhancement, and boundary layer thickness., 資料番号: AA0028635000, レポート番号: NAL SP-46

航空宇宙技術研究所 17-19 Jan. 2000 東京 日本, National Aerospace Laboratory 17-19 Jan. 2000 Tokyo Japan, ワークショップの各部会における以下の課題について発表された研究が報告されている。(1)一般講義では、「次世代SSTに向けての研究」および「NALのSST研究プロジェクト」、(2)一般部会では、「SSTの設計とCFDに対する必要条件」(3)技術部会1では、「NALのCFD支援設計研究」、「数値最適化」および「多分野にわたる研究」、(4)技術部会2では、「設計のための次世代コンピュータシステム」および「CFDにおける基本的問題」。, Studies on the following topics in each section of the workshop are reported: (1) 'research toward the next generation SST' and 'NAL's SST research project' as general lectures; (2) 'designing SST and requirement on CFD' for the general session; (3) 'NAL's CFD-aided design research', 'numerical optimization' and 'treatment of multidiscipline' for the technical session 1; (4) 'next generation computer system for designing' and 'fundamental problems in CFD' for the technical session 2., 資料番号: AA0028638000, レポート番号: NAL SP-49T

航空宇宙技術研究所 24-26 Jun. 1998 東京 日本, National Aerospace Laboratory 24-26 Jun. 1998 Tokyo Japan, 日本における回転翼機の空力騒音研究についてパネルディスカッションの形式で討論が行われた。パネリストは東京大学、航空宇宙技術研究所、コミュータヘリコプタ先進技術研究所(ATIC)、石川島播磨重工業、川崎重工業、三菱重工業、富士重工業の主な代表者である。議論された内容は、各機関・各社における回転翼騒音研究の概要(機内、機外)、ヘリコプタ騒音の計測技術と対策、CFD(数値流体力学)を含む騒音解析の現状と設計への反映、航技研での回転翼騒音研究の役割と航技研への要望、国内・国外との研究協力および体制である。本報告は、パネルディスカッションでの討論内容を要約したものである。, The aeroacoustic research activity of rotorcraft in Japan has been discussed. The main institutes, universities and companies have participated in the panel discussion, namely Tokyo University, National Aerospace Laboratory, Advanced Technology Institute of Commuter Helicopter (ATIC), Ishikawajima-Harima, Kawasaki, Mitsubishi and Fuji Heavy Industries. The topics to discuss are as follows: the brief talk with the aeroacoustic research activity in each institutes and companies, the measurement technology and its application in each institutes and companies, the present status of aeroacoustic analysis including CFD (Computational Fluid Dynamics) techniques and its application into design, the research activity for rotorcraft aeroacoustics in NAL and its role for other institutes and companies and the research cooperation and its organization with foreign research institutes. This report describes the brief summary of the panel discussion., 資料番号: AA0001958044, レポート番号: NAL SP-41

航空宇宙技術研究所 24-26 Jun. 1998 東京 日本, National Aerospace Laboratory 24-26 Jun. 1998 Tokyo Japan, NALにおいて数値流体力学(CFD)を中心とする数値シミュレーション技術の新しい動向についての特別企画を実行し、多くの分野についての数値シミュレーションの現状と将来を展望した。それぞれの分野での討論会、パネルディスカッションおよびワークショップにおいて、超音速輸送機(SST)、ヘリコプタ回転翼、高エンタルピー流れ、宇宙推進、航空推進、および乱流の遷移構造とその予知、の6分野のテーマについての65の研究を記述した。, A special meeting on new trends of the numerical simulation technologies centered around Computational Fluid Dynamics (CFD) was organized and held at NAL, in which the current status and the future perspective of the technologies over a wide range of research areas were presented. In the discussions, panel discussions and workshops for each area, 65 papers of 6 fields are described, namely, Supersonic Transport (SST), helicopter rotors, high enthalpy flows, spacecraft propulsion, aircraft propulsion, and the transition structure of turbulence and its prediction., 資料番号: AA0001958000, レポート番号: NAL SP-41

航空宇宙技術研究所 12-13 Jun. 1997 東京 日本, National Aerospace Laboratory 12-13 Jun. 1997 Tokyo Japan, CFD(数値流体力学)に関する次の主題を論じている。(1)SST(超音速輸送)、小型高速実験機、SSTの主翼空力設計、ナセルのブリード流/バイパス流効果、(2)高エンタルピー流れ、空力加熱の化学反応モデル、衝撃波誘起非定常空力加熱、(3)航空エンジン/宇宙推進、航空機エンジン内の3次元非定常流れ解析、(4)回転翼、ヘリコプタ・メインロータ周りの流れ、ロータCFDコードの開発、および(5)乱流、圧縮性流体の乱流、平行平板間の乱流熱伝達。, The following subjects on CFD (Computational Fluid Dynamics) are discussed: (1) SST (Supersonic Transport), scaled high-speed experimental aircraft, aerodynamic design of a SST wing, bleed and bypass effects of nacelles; (2) high enthalpy flows, chemical reaction model of aerodynamic heating, shock wave induced unsteady aerodynamic heating; (3) aircraft engine/space propulsion, three dimensional unsteady flow analysis in turbomachinery; (4) rotor, flowfields around main rotor, development of rotor CFD codes, and (5) turbulence, turbulence of compressible flows, turbulent heat transfer in a channel between parallel plates., 資料番号: AA0001433000, レポート番号: NAL SP-37

極超音速飛行実験機(HYFLEX)は、我が国で初めての極超音速揚力飛行を行うことに成功した。この実験機は、無人宇宙往還機に必要な基礎技術を確立するために開発されたものである。本報告では、飛行データの解析により得られた主要な空力特性およびその予測結果との比較を示す。それらは、空力係数、縦トリウム特性、空力微係数、エレボンヒンジモーメント係数、表面圧力分布である。飛行結果と比較した予測値は、風洞試験やCFD(計算流体力学)計算に基づき設定されたものである。比較の目的は、設計の過程における不確定性の設定も含めて、予測法の妥当性を評価することにある。飛行結果は概ね予測値に一致したが、このことは今回使用した予測法が高迎角で飛行する再突入揚力体の設計に有効であることを示している。その一方で、軸力係数、エレボントリム舵角、RCS(ガスジェット姿勢制御システム)ガスジェット干渉について、飛行結果と予測値の間に差が見られたため、それらの原因も考察する。, The Hypersonic Flight Experiment (HYFLEX) vehicle successfully performed a hypersonic lifting flight. The vehicle was developed to establish the basic technologies necessary for an unmanned shuttle vehicle. In this report, the primary aerodynamic characteristics derived from analysis of the flight data are presented. They are aerodynamic force coefficients, longitudinal trim characteristics, stability and control derivatives, elevon hinge moment coefficient, and surface pressure distribution. The flight results are compared with the preflight predictions based on wind tunnel tests and CFD (Computational Fluid Dynamics) calculations. The purpose of the comparison is to evaluate the validity of the prediction methods including the development of aerodynamic uncertainties in the vehicle design process. The flight results agreed well with the predictions. This shows that the prediction methods are generally valid for the design of a lifting reentry vehicle with a high angle of attack. On the other hand, some differences between the flight results and the predictions were found in axial force coefficient, elevon trim deflection, and RCS (Reaction Control Subsystem) gas-jet interaction. The causes of these are also discussed in this report., 資料番号: AA0001262000, レポート番号: NAL TR-1334

航空宇宙技術研究所 6-7 JUN. 1996 東京 日本, National Aerospace Laboratory 6-7 JUN. 1996 Tokyo Japan, 以下の主題を論じた。衝撃波渦捕獲法、壁面乱流、圧縮性ナビエ・ストークス方程式、極超音速飛行実験(HYFLEX)の飛行データ、高エンタルピー流れ、OREX(軌道再突入実験機)周りの非平衡流、超音速翼型の逆解法、翼平面形状の最適化、行列積における並列処理、空間前進法、流路切替え機構、高圧タービン、2重円管内乱流、ヘリコプタ・ロータのBVI(ブレード渦干渉)騒音、近傍場におけるソニックブーム強度、翼周りの非定常粘性流、および極超音速化学平衡流。, The following topics are discussed: shock vortex capturing, wall turbulence, compressible Navier-Stokes equation, flight data of HYFLEX (Hypersonic Flight Experiment), high enthalpy flow, nonequilibrium flow around OREX (Orbital Reentry Experiment), inverse problem for supersonic airfoil, optimization of wing planform, matrix multiplication with parallelized program, space marching method, flow switch device, high pressure turbine, turbulent annular flow, BVI (Blade Vortex Interaction) noise of helicopter rotor, sonic boom intensity in near-field, viscous unsteady flow around wing, and hypersonic chemically equilibrium flow., 資料番号: AA0000685000, レポート番号: NAL SP-34

航空宇宙技術研究所 8 Jun. 1995 東京 日本, National Aerospace Laboratory 8 Jun. 1995 Tokyo Japan, NALでは1995年6月高エンタルピー流れのワークショップを開催し、次の課題を検討した。高温衝撃風洞の駆動気体汚染、単純な物体の周りの高エンタルピー流計算、OREX(軌道再突入実験)の空力、空気熱力学データとOREX飛行実験、衝撃波誘起非定常空力加熱現象、CFD(計算流体力学)と極超音速試験、球体および鈍頭円錐モデルの高エンタルピー空気流、OREX形状、鈍頭体回りの熱化学非平衡極超音速流、OREX回りの極超音速流れ場、OREXおよび双曲面フレア回りの極超音速流、双曲面フレア体回りの極超音速流、など。, The following topics were discussed at the symposium which held in NAL on June, 1995: driver gas contamination in a shock tunnel, high enthalpy flow computation around the simple bodies, aerodynamics of OREX (Orbital Reentry Experiment), aerothermodynamic results and OREX flight experiments, shock wave induced unsteady aerodynamic heating phenomena, CFD (Computational Fluid Dynamics) and hypersonic testing, high enthalpy air flow computation with a sphere and a blunted cone models, OREX configuration, thermochemical nonequilibrium hypersonic flow around blunt body, the hypersonic flow fields around OREX, hypersonic flow around OREX and hyperboloid flare, etc., 資料番号: AA0000110000, レポート番号: NAL SP-29

プリンストン大学A.Jameson教授による招待講演｢航空機用CFDの現状｣を含め合計57件の論文を集めた。取り扱われている課題は、従来の物体回りの流れの数値解析のほか、乱流の直接シミュレーション、ターボジェットおよびラム/スクラムジェットエンジン燃焼器の中の流れ、航空宇宙技術研究所の並列ベクトル計算機システム｢NWT｣の性能評価などを含む。, Altogether 57 papers are collected, among which is the invited lecture by Professor A. Jameson of Princeton University giving an overview of the current status of CFD (Computational Fluid Dynamics) as the aircraft aerodynamic design tool. In addition to the usual computational analysis of external flow, the topics of the papers include the direct numerical simulation of the turbulence, the combustor flows within turbojet as well as ram/scramjet engines and the performance assessment of the NAL parallel vector computer system called, 'NWT'., 資料番号: AA0004174000, レポート番号: NAL SP-27

境界層遷移の解明と制御研究会 航空宇宙技術研究所 20010128-20010130 栃木 日本, NAL Workshop on Investigation and Control of Boundary-Layer Transition National Aerospace Laboratory 20010128-20010130 Tochigi Japan, 資料番号: AA0032827000, レポート番号: NAL SP-54

航空宇宙数値シミュレーション技術シンポジウム2001 航空宇宙技術研究所 20010620-20010622 東京 日本, Aerospace Numerical Simulation Symposium 2001 National Aerospace Laboratory 20010620-20010622 Tokyo Japan, 資料番号: AA0032819000, レポート番号: NAL SP-53

Due to the growing interest from engine and aircraft manufacturers for contra-rotating open rotors (CROR), much effort is presently devoted to the development of reliable computational fluid dynamics (CFD) methodologies for the prediction of performance, aerodynamic loads, and acoustics. Forces transverse to the rotation axis of the propellers, commonly called in-plane forces (or sometimes 1P forces), are a major concern for the structural sizing of the aircraft and for vibrations. In-plane forces impact strongly the stability and the balancing of the aircraft and, consequently, the horizontal tail plane (HTP) and the vertical tail plane (VTP) sizing. Also, in-plane forces can initiate a flutter phenomenon on the blades or on the whole engine system. Finally, these forces are unsteady and may lead to vibrations on the whole aircraft, which may degrade the comfort of the passengers and lead to structural fatigue. These forces can be predicted by numerical methods and wind tunnel measurements. However, a reliable estimation of in-plane forces requires validated prediction approaches. To reach this objective, comparisons between several numerical methods and wind tunnel data campaigns are necessary. The primary objective of the paper is to provide a physical analysis of the aerodynamics of in-plane forces for a CROR in high speed at nonzero angle of attack using unsteady simulations. Confidence in the numerical results is built through a code-to-code comparison, which is a first step in the verification process of in-plane forces prediction. Thus, two computational processes for unsteady Reynolds-averaged Navier–Stokes (URANS) simulations of an isolated open rotor at nonzero angle of attack are compared: computational strategy, open rotor meshing, aerodynamic results (rotor forces, blades thrust, and pressure distributions). In a second step, the paper focuses on the understanding of the key aerodynamic mechanisms behind the physics of in-plane forces. For the front rotor, two effects are predominant: the first is due to the orientation of the freestream velocity, and the second is due to the distribution of the induced velocity. For the rear rotor, the freestream velocity effect is reduced but is still dominant. The swirl generated by the front rotor also plays a major role in the modulus and the direction of the in-plane force. Finally, aerodynamic interactions are found to have a minor effect.