The Study Of Induced Velocity Field And The Initial Trajectory Of The Missile On The Condition Of Coupled Rotor/Airframe Helicopter

Helicopter loaded air-to-air missile is the main weapon for the helicopter in air fight. When a missile is launched for a helicopter, its initial trajectory is influenced remarkably by the helicopter down-wash. This thesis supported by the project"The theory of aerodynamic disturbance under the existence of the rotor-airframe-missile helicopt configuration & the analysis of the missile's initial trajectory on that condition"of Nanjing University of Aeronautics and Astronautics, carries out research on the study of induced velocity field and the initial trajectory of the missile on the condition of coupled rotor/airframe helicopt.This thesis includes four parts,First, according to the comparison of different analytical method of wake,a free wake method with fast convergence is established, and some problems concerned with the model are expounded. Some armed helicopter down-wash is calculated.Second, a three-dimensional body panel model with rotor-body coupling is established. The method to make panels and to calculate the panel intensity is provided. A rotor-body coupling model is established, and the method to calculate rotor-body configuration interference flowfield is provided.Third, an engineering applied method to calculate missile's aerodynamic characteristics with rotor-body configuration interference is developed.Finally, the mathematical model of missile motion in helicopter's down-wash flowfield is established. Coupling calculation method of missile's aerodynamic characteristics and initial trajectory with rotor-airframe configuration interference is provided. The aerodynamic and trajectory parameters of the helicopter loaded missile with different original velocity, different launching angle are calculated and analysed.