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arXiv · 2009.14531

Contactless rheology of finite-size air-water interfaces

Vincent Bertin·Zaicheng Zhang·Rodolphe Boisgard·Christine Grauby-Heywang·Elie Raphael·Thomas Salez·Abdelhamid Maali
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Abstract

We present contactless atomic-force microscopy measurements of the hydrodynamic interactions between a rigid sphere and an air bubble in water at the micro-scale. The size of the bubble is found to have a significant effect on the response due to the long-range capillary deformation of the air-water interface. To rationalize the experimental data, we develop a viscocapillary lubrication model accounting for the finite-size effect. The comparison between experiments and theory allows us to measure the air-water surface tension, without contact, paving the way towards robust contactless tensiometry of polluted air-water interfaces.

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Vincent Bertin, Zaicheng Zhang, Rodolphe Boisgard, Christine Grauby-Heywang, Elie Raphael, Thomas Salez, Abdelhamid Maali. 2020-09-30. Contactless rheology of finite-size air-water interfaces. https://doi.org/10.1103/physrevresearch.3.l032007

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