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arXiv · 2409.15083

Phenomenology of laminar acoustic streaming jets

Bjarne Vincent·Daniel Henry·Abhishek Kumar·Valéry Botton·Alban Pothérat·Sophie Miralles
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Abstract

This work identifies the physical mechanisms at play in the different flow regions along an Eckart acoustic streaming jet by means of numerical simulation based on a novel modeling of the driving acoustic force including attenuation effects. The flow is forced by an axisymmetric beam of progressive sound waves attenuating over a significant part of a closed cylindrical vessel where the jet is confined. We focus on the steady, axisymmetric and laminar regime. The jet typically displays a strong acceleration close to the source before reaching a peak velocity. At further distances from the transducer, the on-axis jet velocity smoothly decays before reaching the opposite wall. For each of these flow regions along the jet, we derive scaling laws for the on-axis velocity with the magnitude of the acoustic force and the diffraction of the driving acoustic beam. These laws highlight the different flow regimes along the jet and establish a clear picture of its spatial structure, able to inform the design of experimental or industrial setups involving Eckart streaming jets.

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Bjarne Vincent, Daniel Henry, Abhishek Kumar, Valéry Botton, Alban Pothérat, Sophie Miralles. 2024-09-23. Phenomenology of laminar acoustic streaming jets. https://doi.org/10.1103/ylrm-gsxl

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