Tunable acoustic transmission control and dual-mode ventilated sound insulation by a coupled acoustic metasurface
Siyuan Gao, Xinghao Hu, Youyu Mo, Haohan Zeng, Feilong Mao, Yifan Zhu, Hui Zhang
Abstract
In this paper, we present an alternative design for an acoustic metasurface with sparse units featuring open-ended pipes located on both sides of a central cavity, which can be tuned by designing the widths and length sizes. Band-stop and band-pass transmission control can be easily attained by alternating these units' periodic arrangements with and without intervals and can be theoretically computed by the transfer-matrix method. By combining four of these units, the formed coupled metasurface has a subwavelength of 0.127\ensuremath{\lambda} and can insulate broadband sound (4.2 cm for approximately 1000--1500 Hz). The working bandwidth is between the resonant frequencies of monopolar and dipolar modes, which correspond to a negative effective bulk modulus and a negative effective-mass density, respectively, whose mechanism is different from conventional ones. To help with the tuning, the acoustic-electrical analogy gives the operating frequency as a function of size parameters. Numerical simulations and experiments are used to verify the ventilated sound insulation and transmission control capabilities. This paper presents a structurally simple, lightweight, and multifunctional design with appropriate arrangements that can be applied to acoustic communications, architectural acoustics, noise control, and other related fields.