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arXiv · 1706.08113

Sub-wavelength focusing of acoustic waves in bubbly media

Habib Ammari·Brian Fitzpatrick·David Gontier·Hyundae Lee·Hai Zhang
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Abstract

The purpose of this paper is to investigate acoustic wave scattering by a large number of bubbles in a liquid at frequencies near the Minnaert resonance frequency. This bubbly media has been exploited in practice to obtain super-focusing of acoustic waves. Using layer potential techniques we derive the scattering function for a single spherical bubble excited by an incident wave in the low frequency regime. We then derive the point scatter approximation for multiple scattering by N bubbles. We describe several numerical experiments based on the point scatterer approximation that demonstrate the possibility of achieving super-focusing using bubbly media.

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Habib Ammari, Brian Fitzpatrick, David Gontier, Hyundae Lee, Hai Zhang. 2017-06-25. Sub-wavelength focusing of acoustic waves in bubbly media. https://doi.org/10.1098/rspa.2017.0469

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