AUTHOR=Xu Yu-wei , Guan Yi-jun , Yin Jia-li , Ge Yong , Sun Hong-xiang , Yuan Shou-qi , Liu Xiao-jun TITLE=Low-Frequency Dual-Band Sound Absorption by Ultrathin Planar Wall Embedded With Multiple-Cavity Resonators JOURNAL=Frontiers in Physics VOLUME=10 YEAR=2022 URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2022.911711 DOI=10.3389/fphy.2022.911711 ISSN=2296-424X ABSTRACT=

We report the numerical and experimental realization of a type of ultrathin planar wall with low-frequency dual-band sound absorption. The proposed planar wall is constructed by a periodic subwavelength unit cell (with a thickness of λ/19) which consists of two different multiple-cavity resonators embedded into a plate structure with a groove. The sound absorption of the wall exists in two working bands (IandII) below 600 Hz which are created by two different mechanisms. In addition to the band I created by a conventional resonance coupling of the two multiple-cavity resonators, it is worth noting that the band II is realized by a mutual resonance coupling between the resonators and groove structure. The fractional bandwidths of the bands I and II can reach about 34.1 and 10.4%, respectively. Furthermore, the application of the proposed ultrathin planar wall in the design of a barrier-free anechoic room with omnidirectional low-frequency dual-band sound absorption is further discussed in detail. The proposed planar wall has the advantages of ultrathin planar structure and omnidirectional low-frequency dual-band sound absorption, which provides diverse routes to design advanced sound-absorption structures in noise control and architectural acoustics.