Broadband Vibration Attenuation Achieved by 2D Elasto-Acoustic Metamaterial Plates with Rainbow Stepped Resonators

Abstract

This paper investigates the influences of nonperiodic rainbow resonators on the vibration attenuation of two-dimensional metamaterial plates. Rainbow metamaterial plates composed of thin host plates and nonperiodic stepped resonators are considered and compared with periodic metamaterial plates. The metamaterial plates are modelled with the finite element modelling method and verified by the plane wave expansion method. It was found that the rainbow metamaterial plates with spatially varying resonators possess broader vibration attenuation bands than the periodic metamaterial plate with the same host plates and total mass. The extension of attenuation bands was found not to be attributed to the extended bandgaps for the two-dimensional metamaterial plates, as is generally believed for a one-dimensional metamaterial beam. The complete local resonance bandgap of the metamaterial plates is separated to discrete bandgaps by the modes of nonperiodic resonators. Although the additional modes stop the formation of integrated bandgaps, the vibration of the plate is much smaller than that of resonators at these modal frequencies, the rainbow metamaterial plates could have a distinct vibration attenuation at these modal frequencies and achieve broader integrated attenuation bands as a result. The present paper could offer a new idea for the development of plate structures with broadband vibration attenuation by introducing non-periodicity.

Numerical and Experimental Study of Low-Frequency Membrane Damper for Tube Vibration Suppression

“…A sensitivity analysis on absorber resonant frequencies reveals significant sensitivity in the stopband regions. Wei [17] reported the vibration attenuation of 2D rainbow metamaterial plates with spatially varying stepped resonators. It is found that rainbow resonators can lead to broader vibration attenuation bands compared to periodic resonators.…”

A Finite/Spectral Element Hybrid Method for Modeling and Band-Gap Characterization of Metamaterial Sandwich Plates

“…Elastic/mechanical/acoustic metamaterial structures [ 1 , 2 , 3 ], generally composed of periodically arranged substructures in the form of sandwich structures [ 4 , 5 , 6 ], have special mechanical properties. It is a research hotspot in the fields of mechanics, materials, physics and engineering in recent years [ 7 , 8 , 9 , 10 ].…”

Mechanical Shunt Resonators-Based Piezoelectric Metamaterial for Elastic Wave Attenuation

“…Phononic crystals and metamaterials have attractive potential in elastic wave manipulation and attenuation [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ]. They show promising advantages in the applications of negative refraction [ 2 , 3 ], acoustic cloaking [ 4 , 5 ], wave focusing [ 6 , 7 , 8 , 9 , 10 ], wave attenuation [ 11 , 12 , 13 , 14 , 15 , 16 , 17 ], and vibration-mode tailoring [ 18 ]. The features of phononic crystals and metamaterials stem from Bragg scattering and local resonance, respectively [ 19 , 20 , 21 , 22 , 23 ].…”

“…In addition, it was demonstrated that the width of the bandgap of metamaterials, i.e., the frequency range of wave attenuation, is expandable by structural parametric optimization [ 12 ]. It is worth mentioning that the frequency range of wave attenuation is expandable by adopting rainbow resonators [ 15 , 16 ]. In the past, the metamaterials were assembled by local mechanical resonators integrated into primary structures [ 12 , 25 , 30 , 31 ].…”