Design of a Magnetic Interaction-Based Vibration Absorber for Continuous Beam

Guyue Jiao

doi:10.1155/2020/6384308

Abstract

Classical absorber for vibration suppression of a continuous structure is constructed as a spring-mass oscillator, which only provides coupling force to suppress the vibration of primary structure. In this study, absorber beam is introduced and coupled on the continuous primary beam with magnetic interaction. Thus, the magnetic interaction and coupling bending moment affect the responses of primary beam. Based on the model of the system and Galerkin truncation, the natural frequencies for different magnetic parameters are obtained, which demonstrates that the fundamental frequency can be reduced to zero and the vibration of primary beam can be suppressed in a wide frequency band. Considering the vibration suppression on frequency band, we propose two criteria to evaluate the vibration suppression effect: one is the width of band for vibration suppression and the other is the width for vibration absorption. The two criteria not only show the vibration reduction effect but also correspond to different vibration suppression mechanism. Due to the advantages of zero fundamental frequency induced by the proposed magnetic interaction coupling and wide vibration suppression frequency band, utilizing absorber beam in vibration suppression of continuous structure has potential applications for flexible aim in the fields of manufacturing and aerospace.

Highlights

Due to urgent requirements and harsh conditions in the vibration suppression techniques in the fields of aerospace [1], shipping engineering [2], and ocean platforms [3, 4], it needs the remarkable vibration suppression effectiveness in a wide frequency band
E absorber beam is coupled on continuous beam by crosssection-fixed-connection and magnetic interaction; the mutual effect of the primary beam and absorber beam contains both shear force and bending moment. e following conclusions can be drawn based on our results and discussions: (a) Based on the interaction force model of magnets and the dynamical model of the system, discrete dynamic equation for each order of the system is obtained
(b) With the response solutions solved, since the magnetic interaction is local and nonlinear, the values of the resonance peaks can be suppressed much lower than the case without magnetic interaction for appropriate magnetic structural parameters. e amplitude-frequency curves for different structural parameters reveal that the coupling interaction, especially the bending moment, applied on the primary beam by the absorber beam remarkably suppresses the vibration responses of the primary beam

Summary

Introduction

Due to urgent requirements and harsh conditions in the vibration suppression techniques in the fields of aerospace [1], shipping engineering [2], and ocean platforms [3, 4], it needs the remarkable vibration suppression effectiveness in a wide frequency band. The stiffness and damping of the vibration absorber should have tunable property to result in antiresonance at the required frequencies for the realization of optimal vibration suppression effectiveness. It can be seen that the structural design or control strategy for vibration suppression by both frequency tuning and amplitude reduction is well needed. It requires lightweight TVA with appropriate nonlinearity. E negative stiffness components are two pairs of magnets with very small mass assembled symmetrically on the absorber beam and the free end of the primary beam, adjustable for different structural parameters.

Structure of System Coupled by Magnetic Interaction

Isolation Effectiveness

Input voltage

Conclusions