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=Volume 10 - 2022

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 below 600 Hz which are created by two different mechanisms, such as a mutual coupling of two eigenmodes of multiple-cavity resonators and the eigenmode of a whole structure of the unit cell, and the fractional bandwidths of both bands can reach about 34.1% and 10.4%. 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.