Unique lift-off of droplet impact on high temperature nanotube surfaces
Date of Issue2017
School of Mechanical and Aerospace Engineering
Energy Research Institute @NTU
A unique liquid film lift-off during a falling water droplet impacting on a heated titanium oxide nanotube surface has been experimentally revealed through a high speed visualization system. It is suggested that the Leidenfrost point on the nanotube surface has been significantly delayed, as compared to that on the bare titanium surface. Such delay is inferred to be a result of the increase in the surface wettability and the capillary effect by the nanoscale tube structure. By measuring the liquid lift-off distance from the substrate surface, a droplet lift-off is typically divided into four stages, namely, first contact, first lift-off, second contact, and second lift-off. The residence time at each stage is quantitatively evaluated. As the surface temperature increases, the duration time is significantly reduced for both the first contact and the first lift-off stages.
Applied Physics Letters
© 2017 The Authors (Published by AIP Publishing). This paper was published in Applied Physics Letters and is made available as an electronic reprint (preprint) with permission of The Authors (Published by AIP Publishing). The published version is available at: [http://dx.doi.org/10.1063/1.4994022]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.