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arXiv · 1909.13540

Hydrodynamic response of a surfactant-laden interface to a radial flow

T. Bickel·J. -C. Loudet·G. Koleski·B. Pouligny
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Abstract

We study the features of a radial Stokes flow due to a submerged jet directed toward a liquid-air interface. The presence of surface-active impurities confers to the interface an in-plane elasticity that resists the incident flow. Both analytical and numerical calculations show that a minute amount of surfactants is enough to profoundly alter the morphology of the flow. The hydrodynamic response of the interface is affected as well, shifting from slip to no-slip boundary condition as the surface compressibility decreases. We argue that the competition between the divergent outward flow and the elastic response of the interface may actually be used as a practical way to detect and quantify a small amount of impurities.

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T. Bickel, J. -C. Loudet, G. Koleski, B. Pouligny. 2019-09-30. Hydrodynamic response of a surfactant-laden interface to a radial flow. https://doi.org/10.1103/physrevfluids.4.124002

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