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arXiv · 1811.03915

A mechanism for damage spread by ultrasound-induced linear defects in soft materials

Pooya Movahed·Jonathan B. Freund
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Abstract

High-intensity ultrasound excites pre-existing bubbles in tissue-like material, and the subsequent bubble activity may lead to damage. To investigate such damage mechanisms, agar tissue-mimicking phantoms were subjected to multiple pressure wave bursts of the kind being considered specifically for burst wave lithotripsy (BWL). A notable feature of these experiments was the formation of distinct linear defects, as might expected for a crack. We propose a physical mechanism for how a single bubble, excited by ultrasound, may evolve to from such features. It entails fracture, bubble stability and rectified mass diffusion. These observed linear defects are a potential mechanism for spread of ultrasound-induced bubbles and the subsequent damage.

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Pooya Movahed, Jonathan B. Freund. 2018-11-09. A mechanism for damage spread by ultrasound-induced linear defects in soft materials. https://arxiv.org/abs/1811.03915

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