DataSheet1_Low-Frequency Dual-Band Sound Absorption by Ultrathin Planar Wall Embedded With Multiple-Cavity Resonators.docx

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.

本报告阐述了超薄平面壁低频双频带吸声特性的数值与实验实现。所提出的平面壁由周期性亚波长单元（厚度为λ/19）构成，该单元包含两个不同多腔谐振器，并嵌入带有凹槽的板结构中。该壁的吸声特性存在于两个工作频带（I和II）以下600Hz范围内，这两个频带分别由两种不同的机制产生。除了由两个多腔谐振器传统共振耦合形成的频带I之外，值得注意的是，频带II是通过谐振器与凹槽结构之间的互共振耦合实现的。频带I和II的分数带宽分别可达约34.1%和10.4%。此外，关于所提出的超薄平面壁在无回声室设计中的应用，特别是在实现全向低频双频带吸声方面的详细讨论也被进一步阐述。该平面壁具有超薄平面结构和全向低频双频带吸声的优点，为噪声控制和建筑声学领域先进吸声结构的设计提供了多元化的途径。