Overcoming bandwidth limitations in space-coiled acoustic metamaterials through inclined perforated plate design

Abstract Traditional space-coiled acoustic metamaterials have been widely used in the fields of low-frequency sound absorption and noise reduction. However, they have limitations in terms of low-frequency absorption bandwidth, and the weak coupling effect under complex coiled structures also limits their applications. In this work, we introduce the composite structure changing the characteristic impedance of acoustic metamaterials to enhance the coupling effect. Meanwhile, the perforated plates with inclined design instead of traditional partitions greatly improve the sound absorption. The model and method designed in this paper show significant innovation in enhancing low-frequency absorption performance.