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flight Characteristics Analysis Based on QAR Data of a Jet Transport During Landing at a High-altitude Airport

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Chinese Journal of Aeronautics 2012年第1期25卷 13-24页

作者： C.Edward Lan WU Kaiyuan YU Jiang Department of Aerospace Engineering The University of KansasKansas 66045USA China Aerodynamics Research and Development Center Mianyang 622661China Scientific Research Base Civil Aviation Flight University of ChinaGuanghan 618307China

flight data of a twin-jet transport aircraft in revenue flight are analyzed for potential safety problems. Data from the quick access recorder （QAR） are first filtered through the kinematic compatibility analysis. The filtered data are then organized into longitudinal- and lateral-directional aerodynamic model data with dynamic ground effect. The dynamic ground effect requires the radio height and sink rate in the models. The model data are then refined into numerical models through a fuzzy logic algorithm without data smoothing in advance. These numerical models describe nonlinear and unsteady aerodynamics and are used in nonlinear flight dynamics simulation. For the jet transport under study, it is found that the effect of crosswind is significant enough to excite the Dutch roll motion. Through a linearized analysis in flight dynamics at every instant of time, the Dutch roll motion is found to be in nonlinear oscillation without clear damping of the amplitude. In the analysis, all stability derivatives vary with time and hence are nonlinear functions of state variables. Since the Dutch roll motion is not damped despite the fact that a full-time yaw damper is engaged, it is concluded that the design data for the yaw damper is not sufficiently realistic and the contribution of time derivative of sideslip angle to damping should be considered. As a result of nonlinear flight simulation, the vertical wind acting on the aircraft is estimated to be mostly updraft which varies along the flight path before touchdown. Varying updraft appears to make the descent rate more difficult to control to result in a higher g-load at touchdown.

关键词： jet transport unsteady aerodynamics nonlinear aerodynamics flight dynamics flight safety quick access recorder data

Control-oriented Modeling for Air-breathing Hypersonic Vehicle Using Parameterized Configuration Approach

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Chinese Journal of Aeronautics 2011年第1期24卷 81-89页

作者： LI Huifeng LIN Ping XU Dajun School of Astronautics Beijing University of Aeronautics and Astronautics Beijing 100191 China

This article presents a parameterized configuration modeling approach to develop a 6 degrees of freedom （DOF） rigid-body model for air-breathing hypersonic vehicle （AHV）. The modeling process involves the parameterized configuration design, inviscous hypersonic aerodynamic force calculation and scramjet engine modeling. The parameters are designed for airframe-propulsion integration configuration, the aerodynamic force calculation is based on engineering experimental methods, and the engine model is acquired from gas dynamics and quasi-one dimensional combustor calculations. Multivariate fitting is used to obtain analytical equations for aerodynamic force and thrust. Furthermore, the fitting accuracy is evaluated by relative error （RE）. Trim results show that the model can be applied to the investigation of control method for AHV during the cruise phase. The modeling process integrates several disciplines such as configuration design, aerodynamic calculation, scramjet modeling and control method. Therefore the modeling method makes it possible to conduct AHV aerodynamics/propulsion/control integration design.

关键词： flight dynamics hypersonic AHV model parameterized configuration design aerodynamics/propulsion integration

flight Controller Design of Transport Airdrop

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Chinese Journal of Aeronautics 2011年第5期24卷 600-606页

作者： CHEN Jie SHI Zhongke School of Automation Northwestern Polytechnical University Xi ＇an 710072 China

During airdrop of heavy load, the flight parameters vary continuously as the load moves in the hold, and change suddenly when the load drops out. This process deteriorates the flight quality and control characteristic as the load becomes heavier. Based on the simplified airdrop flight equations, the backstepping and switch control methods are developed to tackle the flight state holding and disturbance/uncertainty （such as large-scale flight condition, pilot manipulation error, system measure delay, etc.） attenuation problem in this paper. Moreover, these methods can be used as a reference for pilot manipulating during airdrop. With the backstepping theory, an adaptive controller is synthesized moves in the hold, and then a coordinated switch control method is for the purpose of stabilizing the transport when the load used to control the aircraft when the condition jumps from the existence of load at the rear of fuselage to no load in the fuselage. Simulation results show that the proposed controllers not only provide effective state holding during airdrop, but also achieve robust performance within wide flight conditions.

关键词： model flight dynamics pitch control flight control control systems

flight Vehicle Performance and Aerodynamic Control

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Towards real-time pilot-in-the-loop CFD simulations of helicopter/ship dynamic interface

丛书名： AIAA Education Series

2001年

作者： Frederick O. Smetana

ISBN: (数字)9781600861857

ISBN: (纸本)9781563474637

flight Vehicle Performance and Aerodynamic Control is designed to serve as a text for either an 11-week or a 16-week course at the sophomore level. It explains typical methods used to estimate aircraft performance, the theoretical basis of these methods, and how various parameters derived from the aircraft geometry can be used to estimate the requirements of control surfaces and the aerodynamic forces required to actuate these surfaces. This book includes time-tested computer programs that perform the analyses in a manner that reduces student error and improves result accuracy. Because the source code is given, users with a FORTRAN compiler can modify the program to suit particular needs. The major advantage of the software is that more realistic problems may be treated and the effects of parametric programs are more accurate than calculators. The programs are available as executables for Windows machines as well as in ASCII source code versions that can be readily compiled and then executed on Unix, Linux, and Macintosh machines, and on mainframes.

关键词： Aerodynamic Performance Aerodynamics Aeronautical Engineering Aeronautics Aerospace Engineering Aerospace Sciences Aircraft Carriers Aircraft Components and Structure Aircraft Conceptual Design Aircraft Design Aircraft Dynamic Modes Aircraft Engines Aircraft Instruments Aircraft Operations Aircraft Operations and Technology Aircraft Performance Aircraft Stability and Control Aircraft Stabilizer Aircraft Wing Components Aircraft Wing Design Aircrafts Airfoil Airfoil Nomenclature Airspeed Astrodynamics Astronautics Atmospheric Science Aviation Aviation Authorities and Organizations Aviation Safety Avionics Civil Aviation Combat Aircraft Combustion Chambers Compressors Energy Energy Conversion Energy Economics Energy Forms Energy Forms, Production and Conversion Energy Production Fixed-Wing Aircraft flight Control Surfaces flight dynamics flight Mechanics flight Test flight Training Fluid dynamics Fluid Flow Properties Fluid Mechanics Fossil Fuels Fuel Injection Fuels Gas Turbine Guidance, Navigation, and Control Systems Heat Engines Helicopters Hydraulics Hydrodynamics Ignition Systems Jet Aircraft Liquid Fuels Longitudinal Static Stability Military Airbases Military Aircraft Military Aviation Non-Renewable Energy Petroleum Power Station Propulsion and Power Reciprocating Engine Rocket Engine Rocketry Rotorcrafts Sensors Short Takeoff and Landing Takeoff and Landing Transducers Turbines Turbomachinery Unmanned Aerial Vehicle Wind Engineering Wind Tunnels Wind Turbine Wing Configurations Wing Planforms

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International Journal of Modeling, Simulation, and Scientific Computing 2017年第4期8卷 64-88页

作者： Ilker Oruc Joseph F.Horn Jeremy Shipman Susan Polsky Department of Aerospace Engineering The Pennsylvania State University University Park PA 16802USA CRAFT Tech PipersvillePA 18947USA NAVAIR Paxutent RiverMD 20670USA

This study presents the development of computationally efficient coupling of Navier–Stokes Computational Fluid dynamics(CFD)with a helicopter flight dynamics model with the ultimate goal of real-time simulation of airwake effects in the helicopter/ship Dynamic Interface(DI).The flight dynamics model is free to move within a computational domain,where the main rotor forces are converted to source terms in the momentum equations of the CFD solution using an actuator disk model.Simultaneously,the CFD solver calculates induced velocities that are fed back to the simulation and affect the aerodynamic loads in the flight dynamics.The CFD solver models the inflow,ground effect and interactional aerodynamics in the flight dynamics simulation,and these calculations can be coupled with the solution of the external flow(e.g.,ship airwake effects).The simulation framework for fully-coupled pilot-in-the-loop(PIL)flight dynamics/CFD is demonstrated for a simplified shedding wake.Initial tests were performed with 0.38 million structured grid cells running on 352 processors and showed near-real-time performance.Improvements to the coupling interface are described that allow the simulation run at near-real-time execution speeds on currently available computing platforms.Improvements in computing hardware are expected to allow real-time simulations.

关键词： Real-time pilot-in-the-loop computational fluid dynamics(CFD) flight dynamics simulation ship airwake dynamic interface helicopter flight dynamics simulation fully-coupled helicopter/ship

Ecolifter Conceptual Configuration Design and Parameter Analysis

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Journal of Beijing Institute of Technology 2003年第2期12卷 149-153页

作者：唐胜景 School of Mechatronics Engineering

In the phase of conceptually designing, the Ecolifter with three lift surface configuration, the influences of aircraft geometric parameters and configuration such as wing geometric parameters, canard parameters, aircraft center of gravity and engine positions and so on, on flight dynamic stability are discussed with the integrated analysis method. On the basis of the analysis of flight dynamic stability, the suitable wing geometric parameters are given and the improved aircraft configuration is proposed.

关键词： aircraft design transport plane flight dynamics

Modeling and Simulation of Lazy Eight Aircraft Maneuver

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Modeling and Simulation of Lazy Eight Aircraft Maneuver