title: Drag reduction by Leidenfrost vapor layers.
abstract: We demonstrate and quantify a highly effective drag reduction technique that exploits the Leidenfrost effect to create a continuous and robust lubricating vapor layer on the surface of a heated solid sphere moving in a liquid. Using high-speed video, we show that such vapor layers can reduce the hydrodynamic drag by over 85%. These results appear to approach the ultimate limit of drag reduction possible by different methods based on gas-layer lubrication and can stimulate the development of related energy saving technologies.
authors.affiliation: Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia. ivanuriev.vakarelski@kaust.edu.sa
authors.forename: Ivan U
authors.initials: IU
authors.lastname: Vakarelski
authors.forename: Jeremy O
authors.initials: JO
authors.lastname: Marston
authors.forename: Derek Y C
authors.initials: DY
authors.lastname: Chan
authors.forename: Sigurdur T
authors.initials: ST
authors.lastname: Thoroddsen