Acoustic signature of rapid flows

Many violent events such as the crumpling or tearing of paper, the drumming of rain on a roof, the crackling of boiling water, or the fizzing of champagne are recognizable by their acoustic signature. Although it only involves a very small portion of the energy involved in these events, their emission therefore contains information that we seek to decipher by simultaneously analyzing the event and its acoustic radiation.

Can we explain the "plop" of a bursting soap bubble? – In collaboration with Adrien Bussonnière, Arnaud Antkowiak, François Ollivier (Institut d'Alembert) and Michaël Baudoin (IEMN, Université de Lille), we have shown that the acoustic emission accompanying the bursting of a soap bubble in the air is due to the capillary forces exerted on the air by the retracting liquid film and not to Laplace pressure. The detailed analysis of the acoustic signal using 3D acoustic antennas and the fast interferometric imaging of the liquid film made it possible to relate it quantitatively to the out-of-equilibrium dynamics of the surfactant film.

E. Blanc, F. Ollivier, A. Antkowiak, R. Wunenburger, Comment on ``Acoustical Observation of Bubble Oscillations Induced by Bubble Popping'', Physical Review E 91, 036401 (2015).
A. Bussonnière, A. Antkowiak, F. Ollivier, M. Baudoin, R. Wunenburger, Acoustic sensing of forces driving fast capillary flows, Physical Review Letters 124, 084502 (2020).

Aerial and sub-surface acoustic signature of an air bubble bursting the surface of a liquid – The underwater noise emitted by the bubbles resulting from the breaking of the waves constitutes a noise pollution which blurs sonar detection. In collaboration with Mathis Poujol (PhD student), Juliette Pierre, Arnaud Antkowiak and François Ollivier (Institut d'Alembert), we studied the aerial and sub-surface acoustic emission of an air bubble bursting the surface of a liquid. While the aerial emission of the bubble is well described by a Helmholtz resonator model with an unsteady geometry which accounts for the fizz of champagne, its sub-surface emission is enriched by a pressure peak which coincides with the self-similar collapse of the bubble according to a finite-time singular process that we are currently seeking to model theoretically with Nicolas Caillier (PhD student) and Arnaud Antkowiak (Institut d'Alembert).

M. Poujol, R. Wunenburger, F. Ollivier, A. Antkowiak, J. Pierre, The sound of effervescence, Physical Review Fluids 6, 013604 (2021).