Analytical, Numerical and Experimental Study of an Enhanced Nonlinear Energy Sink

Abstract

Based on theoretical and experimental investigations, this paper proposes a nonlinear energy sink (NES) with piecewise linear springs to enhance vibration suppression effects. A cubic nonlinear oscillator is coupled with a piecewise linear spring to form an enhanced NES (E-NES). Without adding a new resonance region and changing the resonance frequency of the primary system, the enhanced NES can achieve better vibration suppression effects. Based on the free vibration and the forced vibration, the influence of piecewise linear stiffness on the vibration suppression is profoundly examined. The results show that the E-NES has a better suppression effect on the vibration of the primary structure than that of the cubic NES in most cases. Furthermore, the piecewise stiffnesses and gap displacements are optimized through the differential evolution algorithm. The best damping effect of the E-NES on the free vibration is presented. However, it also happens that the vibration suppression effect of the E-NES is weaker than that of the conventional NES. Moreover, the experimental results verify the analytical and numerical results. The vibration elimination efficiency of the E-NES exceeds 90%. Therefore, this research on using piecewise springs to enhance the vibration suppression efficiency will attract attention.

Overview of piezoelectric energy harvester based on wind-induced vibration effect

“…The empirical formula for the aerodynamic cross-sectional shape of the different columns has a corresponding structure, especially for D-shaped structures, triangular structures, and elliptical structures. The vibration frequency of the gallop-type energy harvesting device is generally low, the flow velocity width is not more than 50 m/s, and the vibration process is mostly nonlinear vibration [37][38][39][40], the vibration amplitude is large, and the structure is prone to overload. From the above research, it is found that the gallop-type energy collection device has a small structure and high energy conversion efficiency.…”