Euler-buckled beam based nonlinear energy sink for vibration reduction of flywheel system under different excitations

Abstract

This study develops a new class of Euler-buckled beam based nonlinear energy sink (EBNES) with three configurations, which is expected to attenuate the disturbance effects and further enhance vibration suppression under launching and on-orbit loads simultaneously. The effects of different arrangements on amplitude-frequency responses of the primary system are derived and analyzed through complexification-averaging method, and the approximate solutions are verified by fourth-order Runge Kutta method. Comparison results exhibit that the EBNES-I is much more effective with enhanced vibration reduction performance and stability in a broad frequency range. Furthermore, a two-degree-of-freedom dynamic model of the flywheel system, which integrates the EBNES-I and the supporting structure in satellite, is established. The vibration reduction and bifurcation behaviors of the proposed EBNES-I are investigated, and the efficiency of the proposed EBNES-I in vibration reduction of the flywheel is compared to that of a traditional cubic-stiffness-type NES. It is found that the EBNES-I exhibits a good vibration reduction performance on the dynamic responses of the flywheel system in launching and on-orbit stage simultaneously. Additionally, the bifurcations of the coupled system are studied in order to investigate the influences of gravity and excitation amplitudes on the stability of the EBNES. Calculation results provide conditions for occurrence of the saddle-node (SN) and Hopf bifurcations.