Numerical and experimental benchmark solutions on vibration and sound radiation of an Acoustic Black Hole plate

Abstract

Acoustic Black Hole (ABH) has been attracting the ever-increasing attention from the scientific community as a passive, effective and lightweight solution for vibration and noise mitigations of vibrating structures. Most existing work, however, relies on numerical simulations using Finite Element models, except a few cases where alternative methods are attempted. In general, there is a lack of well-calibrated experimental benchmark solutions for model validations and phenomena assertions, especially in 2D cases where precise fabrication of ABH indentations with well-controlled thickness profile is a challenge. In this paper, a rectangular plate embodied with a symmetric circular ABH indentation is meticulously manufactured and experimentally tested in terms of eigen-frequencies, mode shapes, forced vibration response and radiated sound power in a baffled half-space. These results offer useful benchmark solutions for future ABH studies. In particular, experimental results show a high consistency with the ones predicted by the previously developed 2D Daubechies wavelet (DW) model.