Drop Impact on Superheated Surfaces

Date

1/20/2012

Journal Title

Journal ISSN

Volume Title

Publisher

Physical Review Letters

Abstract

At the impact of a liquid droplet on a smooth surface heated above the liquid’s boiling point, the droplet either immediately boils when it contacts the surface (“contact boiling”), or without any surface contact forms a Leidenfrost vapor layer towards the hot surface and bounces back (“gentle film boiling”), or both forms the Leidenfrost layer and ejects tiny droplets upward (“spraying film boiling”). We experimentally determine conditions under which impact behaviors in each regime can be realized. We show that the dimensionless maximum spreading ? of impacting droplets on the heated surfaces in both gentle and spraying film boiling regimes shows a universal scaling with the Weber number We (??We 2/5), which is much steeper than for the impact on nonheated (hydrophilic or hydrophobic) surfaces (??We 1/4). We also interferometrically measure the vapor thickness under the droplet.

Description

Keywords

N/A

Citation

Copyright 2012 Physical Review Letters. Recommended citation: Tran, Tuan, Hendrik JJ Staat, Andrea Prosperetti, Chao Sun, and Detlef Lohse. "Drop impact on superheated surfaces." Physical review letters 108, no. 3 (2012): 036101. DOI: 10.1103/PhysRevLett.108.036101 URL: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.108.036101 Reproduced in accordance with the original publisher’s licensing terms and with permission from the author(s).