The Modeling Of Variable Wind Field And Flight Simulation Of High Span-Chord Ratio Unmanned Air Vehicle

In consideration of the special mission characteristics and technical requirement of High Altitude Long Endurance Unmanned Aerial Vehicle, an authentic real-time and space-time windfield integrated model is accomplished to take atmosphere environment influences into account. At the same time, we should analyze the dynamics the UAV encounters dispersedly, so the "Finite Scale" Aircraft concept is quoted. The focuses of this paper are on flight environment simulation and high span-chord ratio UAV model. The main contents and endeavour of this paper are as follow:1. The flight characteristics of High Altitude Long Endurance UAV are analyzed, several typical kinds of Aeronautical Weather are ingathered, and the vertical distributing model of Large Scale Windfield is established, traditional numerical simulation methods of atmosphere environment are summarized.2. Typical variable windfield models, such as Large Scale Steady Wind Flow, Downburst, Turbulence, Airflow over mountain, are developed and their physical specialities are discussed. Furthermore, simplex modules are integrated to form complex model. Facticity and application technique to flight simulation are discussed.3. Some improvements are developed to traditional particle aircraft model, and dynamic UAV model based on variable windfield and "Finite Scale Aircraft" concept are established, what's more the implement algorithm of "four-point" model are described.4. For the first time, flight simulation related to high span-chord ratio UAV based on variable windfield is executed, the facticity of windfield and its influence to flight performance curve are analyzed.5. The principle and algorithm flow of the whole simulating programme are stated, and flight safety precautions in variable windfield and windshear resistance and alleviation technique are analyzed and summarized.The results show that the wind effects are relatively severe and therefore control system design should take this fully into account. This paper gives significant references for UAV conceptual design, flight mission planning and trajectory controlling system design.