关键词: 直升机, 动稳定性, 叶间减摆器, 非线性动力学, 参数分析

Abstract: An analytical model is presented for nonlinear helicopter rotor/fuselage coupled dynamics with inter-blade lag dampers. Along with the damper linear properties, numerical simulation and time-domain technology are applied in predictions of rotor/fuselage coupled dynamic instabilities and damper loads in forward flight. Effects of the damper configurations and structural parameters on the system dynamic instabilities and the damper loads are studied, and significant effects of the damper kinematic couplings are observed. Advantages of kinematic couplings can be utilized by cautiously selecting the damper attachment offset and its build-in angles with rotor hub plane. Compared with a baseline model （which has no damper attachment offset）, analytical results show that the regressive lag mode damping can be increased about 50%, simultaneously, the damper steady cyclic load amplitude has about 60% decrement for a notional model.

Key words: helicopter, dynamic stability, inter-blade lag damper, nonlinear dynamics, parametric analysis