Azbaid et al Proc ICSV 2015.pdf (601.35 kB)
Experimental investigation of the acoustic black hole for sound absorption in air
conference contributionposted on 2015-08-19, 13:19 authored by Abdelhalim Azbaid El Ouahabi, Victor V. Krylov, Daniel O'BoyDaniel O'Boy
In the present paper, the results of the first experimental investigation of the acoustic black hole for sound absorption in air are described. To achieve the required power-law decrease in sound velocity with propagation distance the inhomogeneous acoustic waveguides earlier proposed by Mironov and Pislyakov (2002) and made of quasi-periodic ribbed structures materialising walls of variable impedance have been used. Two different samples of acoustic black holes formed by these ribbed structures have been manufactured to provide linear and quadratic decreases in acoustic wave velocity with distance. Small pieces of absorbing porous material have been inserted at the end. Measurements of the reflection coefficients for guided acoustic modes incident on the black holes have been carried out in the frequency range of 100-1000 Hz. The results show the possibility of significant reduction in the acoustic reflection without using additional absorbing materials. However, contrary to the expectations, the introduction of absorbing materials did not cause further noticeable reduction in the sound reflection coefficients.
- Aeronautical, Automotive, Chemical and Materials Engineering
- Aeronautical and Automotive Engineering
Published inThe 22nd International Congress on Sound and Vibration Proceedings of the 22nd International Congress on Sound and Vibration
Pages? - ? (8)
CitationAZBAID EL OUAHABI, A., KRYLOV, V.V. and O'BOY, D.J., 2015. Experimental investigation of the acoustic black hole for sound absorption in air. Proceedings of the 22nd International Congress on Sound and Vibration, Florence, Italy, 12th-16th July 2015, 8pp.
PublisherInternational Institute of Acoustics and Vibration
- AM (Accepted Manuscript)
Publisher statementThis work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/
NotesThis is a conference paper.