The University of Southampton
University of Southampton Institutional Repository

A comparison of impedance boundary conditions for flow acoustics

A comparison of impedance boundary conditions for flow acoustics
A comparison of impedance boundary conditions for flow acoustics
Acoustic liners remain a key technology for reducing community noise from aircraft engines. The choice of optimal impedance relies heavily on the modeling of sound absorption by liners under grazing flows. The Myers condition assumes an infinitely thin boundary layer, but several impedance conditions have recently been proposed to include a small but finite boundary layer thickness. This paper presents a comparison of these impedance conditions against an exact solution for a simple benchmark problem and for parameters representative of inlet and bypass ducts on turbofan engines. The boundary layer thickness can have a significant impact on sound absorption, although its actual influence depends strongly on the details of the incident sound field. The impedance condition proposed by Brambley seems to provide some improvements in predicting sound absorption compared to the Myers condition. The boundary layer profile is found to have little influence on sound absorption
0022-460X
714-724
Gabard, G.
bfd82aee-20f2-4e2c-ad92-087dc8ff6ce7
Gabard, G.
bfd82aee-20f2-4e2c-ad92-087dc8ff6ce7

Gabard, G. (2013) A comparison of impedance boundary conditions for flow acoustics. Journal of Sound and Vibration, 332 (4), 714-724. (doi:10.1016/j.jsv.2012.10.014).

Record type: Article

Abstract

Acoustic liners remain a key technology for reducing community noise from aircraft engines. The choice of optimal impedance relies heavily on the modeling of sound absorption by liners under grazing flows. The Myers condition assumes an infinitely thin boundary layer, but several impedance conditions have recently been proposed to include a small but finite boundary layer thickness. This paper presents a comparison of these impedance conditions against an exact solution for a simple benchmark problem and for parameters representative of inlet and bypass ducts on turbofan engines. The boundary layer thickness can have a significant impact on sound absorption, although its actual influence depends strongly on the details of the incident sound field. The impedance condition proposed by Brambley seems to provide some improvements in predicting sound absorption compared to the Myers condition. The boundary layer profile is found to have little influence on sound absorption

Text
gabard13.pdf - Version of Record
Download (727kB)

More information

Published date: 18 February 2013
Organisations: Acoustics Group

Identifiers

Local EPrints ID: 351924
URI: http://eprints.soton.ac.uk/id/eprint/351924
ISSN: 0022-460X
PURE UUID: 006ccd8b-1ae0-4661-b3ab-7eb1a2013d99

Catalogue record

Date deposited: 29 Apr 2013 10:18
Last modified: 14 Mar 2024 13:45

Export record

Altmetrics

Contributors

Author: G. Gabard

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×