The University of Southampton
University of Southampton Institutional Repository

The influence of radiation damping on through-resonance variation in the scattering cross-section of gas bubbles

The influence of radiation damping on through-resonance variation in the scattering cross-section of gas bubbles
The influence of radiation damping on through-resonance variation in the scattering cross-section of gas bubbles
When a gas bubble in water undergoes forced pulsations, sound is radiated at the forcing frequency, and the scattering cross-section exhibits a resonance peak when the forcing frequency passes through the bubble’s natural frequency. At resonance, the amplitude of the scattered spherical wave is determined by the amount of damping associated with the bubble dynamics. In his 1967 article, ‘Sound propagation in the presence of bladder fish’, Weston describes a model for the through-resonance frequency dependence of the scattering and extinction cross-sections, based on the work of Andreeva (1964). In Weston’s model, if all damping terms other than radiation damping are omitted, the resonance peak is skewed, with a tendency for the scattering cross-section to increase with increasing frequency through resonance. In 1977, Medwin published ‘Acoustical determination of bubble-size spectra’, based on Eller (1970), in which he describes a similar model, according to which the predicted resonance peak is also skewed, but in the opposite direction to that predicted by Weston. If Medwin’s model turns out to be valid, this would have little impact, as his curves are already in widespread use. However, if the Andreeva-Weston model is correct, a small adjustment becomes necessary to Medwin’s curves. A possible experiment designed to establish the true frequency dependence is described, involving the ensonification of a single spherical bubble with a broadband pulse, through the bubble’s resonance frequency. If the radiation damping can be separated form other effects, the correct frequency dependence can be established by measuring the spectrum of the scattered sound.
bubbles, scattering cross-section, extinction cross-section, radiation damping
571-576
Institute of Sound and Vibration Research
Ainslie, M.A.
ef0d34f3-87cb-49ec-89ef-ef0e596cd2f6
Leighton, T.G.
3e5262ce-1d7d-42eb-b013-fcc5c286bbae
Papadakis, J.S.
Bjorno, L.
Ainslie, M.A.
ef0d34f3-87cb-49ec-89ef-ef0e596cd2f6
Leighton, T.G.
3e5262ce-1d7d-42eb-b013-fcc5c286bbae
Papadakis, J.S.
Bjorno, L.

Ainslie, M.A. and Leighton, T.G. (2007) The influence of radiation damping on through-resonance variation in the scattering cross-section of gas bubbles. Papadakis, J.S. and Bjorno, L. (eds.) In Proceedings of the Second International Conference on Underwater Acoustic Measurements, Technologies and Results. Institute of Sound and Vibration Research. pp. 571-576 .

Record type: Conference or Workshop Item (Paper)

Abstract

When a gas bubble in water undergoes forced pulsations, sound is radiated at the forcing frequency, and the scattering cross-section exhibits a resonance peak when the forcing frequency passes through the bubble’s natural frequency. At resonance, the amplitude of the scattered spherical wave is determined by the amount of damping associated with the bubble dynamics. In his 1967 article, ‘Sound propagation in the presence of bladder fish’, Weston describes a model for the through-resonance frequency dependence of the scattering and extinction cross-sections, based on the work of Andreeva (1964). In Weston’s model, if all damping terms other than radiation damping are omitted, the resonance peak is skewed, with a tendency for the scattering cross-section to increase with increasing frequency through resonance. In 1977, Medwin published ‘Acoustical determination of bubble-size spectra’, based on Eller (1970), in which he describes a similar model, according to which the predicted resonance peak is also skewed, but in the opposite direction to that predicted by Weston. If Medwin’s model turns out to be valid, this would have little impact, as his curves are already in widespread use. However, if the Andreeva-Weston model is correct, a small adjustment becomes necessary to Medwin’s curves. A possible experiment designed to establish the true frequency dependence is described, involving the ensonification of a single spherical bubble with a broadband pulse, through the bubble’s resonance frequency. If the radiation damping can be separated form other effects, the correct frequency dependence can be established by measuring the spectrum of the scattered sound.

Full text not available from this repository.

More information

Published date: 2007
Venue - Dates: 2nd International Conference & Exhibition on "Underwater Acoustic Measurements: Technologies & Results", 2007-06-25 - 2007-06-29
Keywords: bubbles, scattering cross-section, extinction cross-section, radiation damping

Identifiers

Local EPrints ID: 49413
URI: https://eprints.soton.ac.uk/id/eprint/49413
PURE UUID: 3b2b3b39-2b8c-4e7d-a552-01204e13b627
ORCID for T.G. Leighton: ORCID iD orcid.org/0000-0002-1649-8750

Catalogue record

Date deposited: 12 Nov 2007
Last modified: 14 Mar 2019 01:53

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.

×