Geometry of the vapor layer under a Leidenfrost hydrogel sphere
arXiv:2507.04982
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
Figures 2 and 4 were updated, and the text was updated to correspond with the updated figures