非线性减振器抑制旋转叶片受迫振动响应

Forced vibration suppression of a rotating blade by a nonlinear absorber

采用非线性减振器NES(Nonlinear Energy Sink)抑制旋转叶片的受迫振动响应。首先采用拟Hamilton原理建立了旋转叶片与NES耦合系统的动力学方程,并采用Galerkin离散得到了系统的非线性常微分方程组。而后采用谐波平衡法求得了旋转叶片受迫振动一阶响应幅值的解析表达式。最后分别讨论了转速、NES质量、阻尼、非线性刚度和安装位置对振动抑制的影响。分析发现,NES能够随着转速的变化自动匹配叶片的共振频率,从而起到降低叶片共振响应的作用。另外,增大NES质量、阻尼、非线性刚度或将NES安装在靠近叶片自由端都能有效降低叶片的共振响应。

In this paper, forced vibration suppression of a rotating blade by a nonlinear absorber （NES,Nonlinear Energy Sink） is investigated. Firstly, the quasi-Hamilton5s principle is used to model a rotatingblade coupled with a NES, and the Galerkin method is applied to obtain the nonlinear ordinary differentialequations. Then, the harmonic balance method is used to obtain the analytic solution of the first orderresponse of the rotating blade. Lastly, the influences of the rotating speed of the blade, the mass ratio,damping, nonlinear stiffness, and the position of the NES on the vibration response of the blade are studied.Results show that NES could automatch the resonant frequency of the blade for different rotating speed. Itcould reduce resonant response of the blade for all the rotating speed. Moreover, increasing the mass ratio,damping, nonlinear stiffness of the NES, or NES locating near the free end of the blade could decrease theresonant response of the blade greatly.