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arXiv · 2507.04982

Geometry of the vapor layer under a Leidenfrost hydrogel sphere

Vicente L. Diaz-Melian·Isaac C. D. Lenton·Jack Binysh·Anton Souslov·Scott R. Waitukaitis
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Abstract

A floating Leidenfrost droplet exhibits curvature inversion of its underside, due to the balance of vapor pressure and surface tension. Using interferometric imaging, we find different behavior for a levitated hydrogel sphere. Curvature inversion is observed briefly just after deposition, but quickly gives way to a steady state with no inversion. We show the essential role of vaporization on shaping the underbelly of the hydrogel, adding a new component to the interplay between vapor pressure and elastic force

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Vicente L. Diaz-Melian, Isaac C. D. Lenton, Jack Binysh, Anton Souslov, Scott R. Waitukaitis. 2025-07-07. Geometry of the vapor layer under a Leidenfrost hydrogel sphere. https://arxiv.org/abs/2507.04982

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