Low-frequency broadband vibration attenuation of sandwich plate-type metastructures with periodic thin-wall tube cores

Huan Zi,Yinggang Li

doi:10.1177/14613484211035583

Abstract

Sandwich structures are widely applied in modern industry such as aerospace, automobile as well as marine structures. However, the vibroacoustic properties of sandwich structures are adversely influenced by low effective mass. In this study, the flexural wave propagation characteristics and vibration mitigation performances of the periodic sandwich plate-type metastructures are investigated. The proposed sandwich plate-type metastructures are constituted of a sandwich plate with periodic thin-wall circular tube cores and periodically attached local stepped resonators. A finite element method combining Solid-Shell coupling numerical method and Bloch theory is presented to calculate the dispersion relations and the displacement fields of the eigenmodes of the infinite periodic sandwich plate-type metastructures. In addition, the acceleration frequency responses and vibration attenuation performances of finite periodic sandwich plate-type metastructures are numerically investigated and compared with the experimental measurements. Furthermore, the influences of geometric parameters on flexural wave band gaps are conducted. Results show that the sandwich plate-type metastructures can yield a low-frequency broad flexural wave band gap, in which the flexural wave propagation is conspicuously suppressed, resulting in significant flexural vibration attenuation. The flexural wave band gap and vibration attenuation performances can be effectively manipulated by designing geometric parameters of the sandwich plate-type metastructures.

Highlights

We investigate the flexural wave propagation and vibration attenuation performances of periodic sandwich metastructures consisting of a sandwich plate with periodic thin-wall circular tube cores and periodic stepped resonators
We can find that broad flexural wave band gap appears in the range of 246 Hz–1067 Hz as shown in the shadow area, which means the flexural wave cannot propagate in the proposed sandwich metastructures in the frequency range
The flexural wave propagation characteristics and vibration mitigation performances of periodic sandwich plate-type metastructures composed of periodic stepped resonators attached on a sandwich plate with periodic thin-wall tube cores are studied numerically and experimentally

Summary

Introduction

Sandwich structures have been widely used in the field of aerospace, high-speed train, and marine structures due to their excellent mechanical performances.[1,2,3,4,5] In addition to their mechanical properties of sandwich structures, increasing attention has been paid to vibration behaviors and sound transmission properties of sandwich structures because lightweight and stiff structures usually suffer from poor vibro-acoustic performances at low frequency resulting in adverse impact on human comfortableness.[6,7,8,9,10] Many researchers focus on flexural vibration (out-of-plane) characteristics of sandwich structures as their multifunction in vibration and sound transmission attenuation.[11,12,13]In recent years, the wave propagation characteristics in elastic metamaterials have attracted extensive attention owing to their sub-wavelength physical characteristics and tremendous potential application in the low-frequency vibration isolation and sound attenuation. Li et al.[36] proposed sandwich plate-type metastructures with thin-wall tube cores and studied the flexural wave propagation properties numerically and experimentally.

Results

Conclusion