A broadband acoustic panel based on double-layer membrane-type metamaterials

Abstract

Low-frequency noise is a growing problem in large structures of modern transportation technologies. In this study, we report a large-scale acoustic panel made of double-layer membrane-type metamaterials (DMAMs) for broadband noise reduction. A complete theoretical model based on the unit cell is fully developed and extended for finite multi-celled membrane-type acoustic metamaterial (MAMs) array. A large-scale acoustic panel constructed from 8 × 8 DMAM unit cells is proposed. To deal with the global compliance of the large-scale support structure, the double-layer panel frame structure with large bending stiffness is designed to shift the global resonances to higher frequencies and provide an efficient way to well maintain the MAM's performance. Moreover, the double-layer configuration further guarantees ultra high transmission loss within the frequency range of interest. Experiments are carried out to validate the analytical and numerical predictions. Excellent transmission loss ranging from 20 to 59 dB within ten third octave bands (0.32–2.5 kHz) is observed, deeply breaking the mass density law. We believe the proposed design and the associated theoretical model could serve as an efficient tool for designing acoustic metamaterial-based panels and soundproof walls with high noise reduction in low/middle frequency regions.

Acoustic Metamaterials for Noise Reduction: A Review

“…In addition, a large acoustic panel made of double‐layer membrane metamaterials (Figure 5h) was developed for broadband noise reduction. [ 106 ] To solve the overall compliance of large‐scale supporting structures, a double‐layer panel frame structure with high bending stiffness was proposed to increase its overall resonance frequency and provide an effective method for maintaining the performance of double‐layer membrane metamaterials. Zhou et al.…”

“…Reproduced with permission. [ 106 ] Copyright 2021, AIP Publishing. i) Low‐frequency acoustic metamaterial membrane type.…”

“…In addition, a large acoustic panel made of double-layer membrane metamaterials (Figure 5h) was developed for broadband noise reduction. [106] To solve the overall compliance of large-scale supporting structures, a double-layer panel frame structure with high bending stiffness was proposed to increase its overall resonance frequency and provide an effective method for maintaining the performance of double-layer membrane metamaterials. Zhou et al proposed a lightweight, flexible, and ultrathin distributed membrane acoustic metamaterial (Figure 5i), [107] which could effectively broaden the sound attenuation zone in the low-frequency range and produce single-negative effective parameter characteristics.…”

Hybrid fractal acoustic metamaterials for low-frequency sound absorber based on cross mixed micro-perforated panel mounted over the fractals structure cavity

“…However, the thickness of the backing cavity is usually more than 5 cm for obtaining a broadband sound absorption behavior. Ultrathin membrane metamaterials (MM) 31 , 32 , are a very good candidate for broadband sound absorption behavior but the problem in MM is membrane loosening effect which may come in due course of time after repeated use.…”

Isolamento acústico de baixa frequência via metapainel de ressonadores de membrana decorada

“…Uma configuração especialmente atraente é a de MAMs na geometria de painéis. Própria para diversas aplicações estruturais, como em aeronaves, veículos e paredes de ambientes fechados, este tipo de montagem de MAMs é largamente investigado (SAMPAIO; CERÂNTOLA; OLIVEIRA, 2022;OLIVEIRA, 2021;NGUYEN et al, 2021;MA et al, 2021;LANGFELDT;ESTORFF, 2018), mas várias questões que impedem a fabricação em larga escala estão ainda por serem resolvidas. O presente trabalho se insere justamente nesta lacuna, visando contribuir para o estado da arte com o projeto de um metapainel aperiódico de DMRs que seja, ao mesmo tempo, esteticamente agradável e acusticamente eficiente.…”