Impact of a superhydrophobic sphere onto water.
نویسندگان
چکیده
When a water drop hits a superhydrophobic solid surface, it bounces off the substrate like an elastic ball. Here we show that when a tiny superhydrophobic solid sphere impacts with water, it can bounce off the free surface just as it impacts with an elastic membrane. The motion of a sinking sphere is analytically calculated by solving a potential flow whose free boundary is determined by the Young-Laplace equation. To find conditions under which the solid sphere should sink, bounce off, or oscillate upon impact with water, we construct simple scaling laws which are shown to agree well with experimentally found boundaries between the distinct impact behaviors in a regime map based on dimensionless parameters.
منابع مشابه
Water entry of a superhydrophobic low-density sphere
This paper virtually demonstrates an air cavity formed by a superhydrophobic low-density sphere entering into water with the use of a high-speed camera. Unlike the previous results for a high-density sphere, the low-density sphere pinches off the resulting air cavity at the shorter depth before the cavity has fully grown, and attracts minimal air on the rear surface due to rapid deceleration of...
متن کاملDrop Impact Study on Flexible Superhydrophobic Surface Containing Micro-Nano Hierarchical Structures
Superhydrophobic surfaces are abundant in nature. Several surfaces such as wings of butterfly, legs of water strider, feet of gecko and the lotus leaf show extreme water repellence behaviour. Self-cleaning, stain-free fabrics, spill-resistant protective wears, drag reduction in micro-fluidic devices etc. are few applications of superhydrophobic surfaces. In order to design robust superhydrophob...
متن کاملAnthraquinone dyes for superhydrophobic cotton.
Water-repellent, self-cleaning and stain resistant textiles are of interest for industrial applications. Anthraquinone reactive dyes were covalently grafted onto cotton fabric surfaces obtaining bright colors with good wash-fastness properties and giving rise to breathable superhydrophobic textiles with self-cleaning properties.
متن کاملImproving the natural convective heat transfer of a rectangular heatsink using superhydrophobic walls: A numerical approach
The effect of utilizing superhydrophobic walls on improving the convective heat transfer in a rectangular heatsink has been studied numerically in this paper. The vertical walls were kept at isothermal hot-and-cold temperatures and horizontal walls were insulated. The boundary condition on the walls was: no-slip for regular, and slip (with slip length of 500 µm) for superhydrophobic walls. By c...
متن کاملSuperhydrophobic surfaces by anomalous fluoroalkylsilane self-assembly on silica nanosphere arrays.
We present the self-assembled formation of nanosized PFDTS (1H,1H,2H,2H-perfluorodecyltrichlorosilane) features on multilayered silica sphere arrays. We reveal the importance of residual water within the microsphere multilayers during PFDTS deposition and discuss a possible mechanism for the formation of the siloxane nanostructures. The multiscaled roughness induced by these superstructures is ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Langmuir : the ACS journal of surfaces and colloids
دوره 24 1 شماره
صفحات -
تاریخ انتشار 2008