Ultra-broadband acoustic ventilation barrier based on multi-cavity resonators

Abstract

We report the numerical and experimental realization of an ultra-broadband acoustic ventilation barrier composed of periodic unit cells. Based on multiple mechanisms, including sound absorption by eigenmodes of the unit cell and sound reflection by a plate structure on upper surface of the unit cell, we design a single-layer ventilation barrier with broadband sound reduction, and the working bandwidth can reach about 1560 Hz. The experimental results agree well with the simulation ones. Furthermore, we design and demonstrate two types of three-layer ventilation barriers by using the unit cells with different values of a (the length of the hollow square region) and w (the width of the channel between the adjacent cavities), and the bandwidths of both ventilation barriers can be increased to 3160 and 3230 Hz, respectively. The designed barrier structures have the advantages of ultra-broadband sound reduction and ventilation, which paves a way to design high-performance ventilation barriers for the application in environmental protection and architectural acoustics.