直升机旋翼叶间减摆器的参数影响分析

建立了带叶间减摆器的直升机旋翼/机体耦合非线性动力学分析模型,针对具有线性特性的叶间减摆器,采用数值模拟及时域方法分析了直升机前飞状态下旋翼/机体耦合动稳定性及减摆器载荷,并就减摆器布局、几何参数对系统动稳定性及减摆器载荷的影响进行了分析。研究发现,"叶间"布局引起的几何耦合对减摆器载荷及系统的动稳定性有很大的影响,合理选择减摆器安装支臂的长度及其与桨毂平面之间的夹角,可以有效地利用几何耦合的因素。与基本模型相比,它能使系统的模态阻尼提高50%以上,而同时使减摆器的定常循环载荷的幅值下降60%左右。

Parametric Analysis of Inter-Blade Lag Dampers of Helicopter Rotor

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.