Vibration mitigation and dynamics of a rotor-blade system with an attached nonlinear energy sink

Abstract

Excessive vibration of rotor-blade systems has been a main reason for the failure of rotating machinery. Therefore, methods capable of simultaneously suppressing vibrations rotor and blade are urgently needed. Considering this, a nonlinear energy sink (NES) with piecewise linear stiffness is used to satisfy the requirements. Firstly, the structure and working mechanism of the NES are introduced. And then, the dynamic model of rotor-blade-NES system is established by Lagrangian method The vibration suppression ability of the NES is studied under transient and steady state excitations. Dynamic behavior of the rotor-blade system with a NES is also investigated through global bifurcation analyses in this work. Finally, a simple test of NES’s vibration suppression ability on rotor-blade system is completed. The results show that, under given parameters, the vibration suppression performances of the NES on both rotor and blade are superior both in steady state and transient state. In numerical simulation, a vibration suppression rate of 93% on the rotor is achieved and in test a rate of 88% is achieved.