风雨严重影响飞机的飞行安全。基于动量定理建立了一种根据降雨条件、风场特性、飞机特征和飞行状态计算雨滴对飞机产生的撞击力和力矩的方法,研究了风雨对飞机气动特性的影响,进而建立了飞机在风雨中飞行的运动方程。通过引入驾驶员的操纵模型,对飞机在风雨中飞行的运动特性进行了数值仿真研究。仿真结果表明:降雨会使飞机的升力减小,阻力增大,平衡迎角增加,不利于飞机的飞行安全;当降雨过程中伴随有风时,风会改变飞机的飞行迎角,使得飞机更容易出现因失速而造成的飞行事故;降雨时飞机的抗风能力降低。
The flight safety of an aircraft is often seriously affected by wind and rain. The method based on momentum theorem to compute the force and moment generated by raindrops considering aircraft characteristics,flight and meteorologic conditions is provided. The impacts of rainfall with wind on the aerodynamic characteristics of an aircraft are studied. And the aircraft flight dynamic equations in rain and wind fields are deve-loped. By introducing a pilot model,the flight dynamic characteristics of an aircraft in the rain and wind fields are numerically simulated. The study shows that the balance attack angle of an aircraft will increase in the rainfall since the lift decreases and the drag increases,which will threaten the aircraft flight safety. When a rain is accompanied by a wind,the attack angle of the aircraft will be changed by the wind,and the aircraft will be more possibly to stall,which may cause a flight accident. The ability of the aircraft to fly safely in a wind will decrease due to rain.