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arXiv · 1202.2157

The Geometry of the Vapor Layer Under a Leidenfrost Drop

J. C. Burton·A. L. Sharpe·R. C. A. van der Veen·A. Franco·S. R. Nagel
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Abstract

In the Leidenfrost effect, liquid drops deposited on a hot surface levitate on a thin vapor cushion fed by evaporation of the liquid. This vapor layer forms a concave depression in the drop interface. Using laser-light interference coupled to high-speed imaging, we measured the radius, curvature, and height of the vapor pocket, as well as non-axisymmetric fluctuations of the interface for water drops at different temperatures. The geometry of the vapor pocket depends primarily on the drop size and not on the substrate temperature.

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J. C. Burton, A. L. Sharpe, R. C. A. van der Veen, A. Franco, S. R. Nagel. 2012-02-10. The Geometry of the Vapor Layer Under a Leidenfrost Drop. https://doi.org/10.1103/physrevlett.109.074301

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