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arXiv · 2002.11058

Suppression of acoustic streaming in shape-optimized channels

Jacob S. Bach·Henrik Bruus
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Abstract

Acoustic streaming is an ubiquitous phenomenon resulting from time-averaged nonlinear dynamics in oscillating fluids. In this theoretical study, we show that acoustic streaming can be suppressed by two orders of magnitude in major regions of a fluid by optimizing the shape of its confining walls. Remarkably, the acoustic pressure is not suppressed in this shape-optimized cavity, and neither is the acoustic radiation force on suspended particles. This basic insight may lead to applications, such as acoustophoretic handling of nm-sized particles, which is otherwise impaired by acoustic~streaming.

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Jacob S. Bach, Henrik Bruus. 2020-02-25. Suppression of acoustic streaming in shape-optimized channels. https://doi.org/10.1103/physrevlett.124.214501

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