变直径倾转旋翼机设计重心包线研究

Research on the design center of gravity envelope of tilt-rotor aircraft with variable diameter

倾转旋翼机具有直升机垂直起降和固定翼高速前飞的特点,而变直径倾转旋翼机可以同时满足其悬停和巡航状态对旋翼的设计要求。基于飞行动力学模型,提出一种倾转旋翼机重心极限及设计重心包线计算方法。以XV-15进行方法验证,分析了旋翼变直径对全机重心包线的影响。结果表明,大直径有利于扩大直升机模式和过渡状态的重心包线,而直径变化对固定翼飞机模式重心包线无影响。

The tilt-rotor aircraft have characteristics of the vertical take-off and landing of helicopters and the high forward-flight speed of fixed-wing aircraft,while the variable diameter tilt-rotor aircraft can satisfy both design requirements for rotors of hovering and cruising performance.This thesis proposes a calculation method for the center of gravity limit of tilt-rotor aircraft and the design of the center of gravity envelope,based on the tilt-rotor aircraft flight dynamics model.Then this thesis verifies the correctness of the method with XV-15,and analyses the effect on the center of gravity of the whole aircraft under the condition of variable diameter of rotors.The result shows that the large diameter rotor is beneficial to expand the range of center of gravity envelop both helicopter mode and transition state,while the diameter change has no effect on the fixed-wing aircraft mode.