Vibro-acoustic performance of acoustic metamaterial plate with periodic lateral local resonator

Abstract

Based on the Bloch theory and the flexural wave propagation theorem, the model for calculating the vibration response, sound radiation power and radiation efficiency of an acoustic metamaterial plate is established. The modal analysis of a bare pate and the plate attached to periodical lateral local resonators are developed to investigate the vibration regulation. In addition, the patterns of the sound radiation power and radiation efficiency of the plate attached to periodical lateral local resonators versus frequency are studied. The results show that 1) in a specific frequency range, the mean square velocity and the sound radiation power are far lower than those of the bare plate, which is due to the resonance of the lateral local resonator; 2) unlike the vibration response and sound radiation power, the radiation efficiency of the plate attached to periodical lateral local resonator is higher than that of the bare plate. The investigation of the plate attached to lateral local resonator in this paper lays a solid foundation for the practical engineering in the field of vibration suppression and noise reduction.

Vibro-Acoustic Performance of a Fluid-Loaded Periodic Locally Resonant Plate

“…Apart from the interior noise reduction of the cavity adjacent to the LR structure, the sound radiation performance in the exterior infinite free space was also examined [38], specifically focusing on the characteristics of radiation efficiency. The authors of the present research also extended the vibro-acoustic research to the LR structures with sandwich units [39], periodic multiple resonators [14], and local lateral resonators [15]. Like the above studies, many works about the flexuralwave band-gap properties and vibro-acoustic performance of LR structures have been conducted.…”

“…However, the properties of flexural-wave-induced sound radiation of underwater LR structures remain unknown, and the effect of heavy water fluid on flexural-wave vibro-acoustic performance needs to be revealed. In the above vibro-acoustic research related to exterior infinite free space [14,15,38,39], the uncoupled vibro-acoustic models were used with the coupling between structure and fluid neglected. The physical models are only appropriate for air-surrounding applications but are inappropriate for water-surrounding applications because of strong structure-fluid coupling.…”

“…Q. Wen et al studied the bending-vibration band structure of a one-dimensional phononic crystal beam composed of periodic resonators with two degrees of freedom, resulting in more abundant and broader band gaps, which is beneficial to multiple-frequency vibration reduction [8]. J. Wu et al extended the one-dimensional beam to a more complicated two-dimensional pate [9], and some other researchers have also conducted related multidegree-of-freedom research [10][11][12][13][14][15]. In addition, nonlinear LR structures [16][17][18][19][20] have also gained extensive attention, broadening the local resonance mechanism's research scope.…”

Method for vibration and acoustic radiation analysis of underwater stiffened plates with acoustic coatings

“…Notably, the simple harmonic excitation is placed in the center of the parent plate with the whole structure being embedded in the infinite rigid baffle. According to the classical plate-shell theory [7][8][9] , the motion equation of the substrate plate is: ( ) ( )…”

“…By virtue of collecting the vibration displacement of the sample surface as well as the underwater acoustic radiation pressure by a vibration sensor and hydrophone respectively, this method can determine the underwater vibroacoustic characteristics of the structure through further data processing. Overall, it is mainly divided into two categories, encompassing the small-sample acoustic tube test and the large-sample anechoic tank test [7][8][9][10] .…”