Bubble clouds as sources and scatterers of underwater sound

Abstract

A model of a bubble cloud based on a set of averaged equations is used to study the acoustic emission and scatteringproperties of these objects. From a study of the normal modes of the cloud, it is inferred that the lowest modes have a frequency much lower than that of the individual bubbles. This indicates that clouds of bubbles can radiate at such low frequencies if these modes are excited. The results of some scattering calculations at different wavelengths are also shown as a function of the incidence and scattering angles. [Work supported by ONR.]