The University of Southampton
University of Southampton Institutional Repository

High intensity sound propagation in flow ducts

High intensity sound propagation in flow ducts
High intensity sound propagation in flow ducts
A theoretical and experimental study of the propagation of finite amplitude pressure waves, or high intensity sound, in flow ducts was undertaken. A quantitative appreciation is presented describing the propagation of such waves including reflections. Observations showed that time domain descriptions are appropriate for the analysis of such waves, for which the well established method of characteristics proved ideal, providing that both the particle velocity and pressure time histories were established simultaneously. Existing techniques for predicting wave propagation in ducts based on the method of characteristics were reviewed and found to be inefficient for noise emission predictions when the velocity time history was not known. The approach described here gave reliable estimates of the velocity-time history at a reference plane in the duct using a pair of pressure-time histories obtained from closely spaced transducers flush mounted in the duct wall. The essential precautions and conditions required for the measurement procedures necessary to maintain confidence in the estimates of the velocity have been identified. Estimates of velocity and pressure time histories at two positions downstream and one upstream of the reference plane were obtained and found to compare well with observations. The appropriate boundary conditions for describing wave reflections at an open duct termination have been established and evaluated for a systematic set of practical excitations.
Yaseen, Ehab Ahmed A.
d161456a-e4f1-42e2-8b42-22c1e1c4e2e5
Yaseen, Ehab Ahmed A.
d161456a-e4f1-42e2-8b42-22c1e1c4e2e5
Davies, P.O.A.L.
e2de24e0-483d-49fb-ad50-703548232c61

Yaseen, Ehab Ahmed A. (1987) High intensity sound propagation in flow ducts. University of Southampton, Institute of Sound and Vibration Research, Doctoral Thesis, 252pp.

Record type: Thesis (Doctoral)

Abstract

A theoretical and experimental study of the propagation of finite amplitude pressure waves, or high intensity sound, in flow ducts was undertaken. A quantitative appreciation is presented describing the propagation of such waves including reflections. Observations showed that time domain descriptions are appropriate for the analysis of such waves, for which the well established method of characteristics proved ideal, providing that both the particle velocity and pressure time histories were established simultaneously. Existing techniques for predicting wave propagation in ducts based on the method of characteristics were reviewed and found to be inefficient for noise emission predictions when the velocity time history was not known. The approach described here gave reliable estimates of the velocity-time history at a reference plane in the duct using a pair of pressure-time histories obtained from closely spaced transducers flush mounted in the duct wall. The essential precautions and conditions required for the measurement procedures necessary to maintain confidence in the estimates of the velocity have been identified. Estimates of velocity and pressure time histories at two positions downstream and one upstream of the reference plane were obtained and found to compare well with observations. The appropriate boundary conditions for describing wave reflections at an open duct termination have been established and evaluated for a systematic set of practical excitations.

Other
000795.PDF - Other
Restricted to Repository staff only

More information

Published date: 1987
Organisations: University of Southampton

Identifiers

Local EPrints ID: 52288
URI: https://eprints.soton.ac.uk/id/eprint/52288
PURE UUID: c41f40d5-e26e-4714-aa7f-72e418e26880

Catalogue record

Date deposited: 26 Aug 2008
Last modified: 13 Mar 2019 20:44

Export record

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 https://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.

×