Tunable Microperforated Panel Acoustic Absorbers with Coupling Effects

Design for highly effective acoustic absorber with broadband sound attenuation is challenging due to the typically large size or intricate internal structures involved. In this study, a tunable microperforated panel (MPP) acoustic absorber is proposed that leverages the coupling effects between its sub-components to achieve broadband sound absorption. The theoretical and numerical models are first presented to evaluate the acoustic properties of the coupled MPP absorbers. The theoretical and numerical analysis clarifies how coupling effects enhance the absorption troughs in the proposed absorber. Subsequently, a parametric study is conducted to demonstrate the potential of broadband sound attenuation of the proposed MPP absorbers. Finally, a compact sound absorber, composed of multiple coupled MPP absorbers, is proposed to achieve broadband sound absorption, especially at low-frequency regime. Experimental investigations validate the sound absorption performance of the proposed sound absorber, highlighting the potential of our theoretical model and coupled MPP absorbers to advance acoustic metamaterials design.