An experimental investigation into a dual taper acoustic black hole termination

Abstract

Acoustic black holes (ABHs) can provide effective damping of the reflected wave component when used to terminate a beam. The behaviour of an ABH is characterised by its local modes, which produce narrow frequency bands of high absorption. To enhance the performance of ABH terminations, a multi-taper ABH has previously been proposed and analytical results demonstrate that the use of two or more tapers produces a compound effect on the reflection coefficient, resulting in more bands of low reflection. This paper extends this work and presents an experimental realisation of a multi-taper ABH confirming the previous analytical results.