Effect of Disk Edge Profile on Scattering Characteristics of Liquid Droplets Splashed from Spinning Disk

Mizue Munekata, Taichi Oseto, Hiroaki Kurishima, Hiroyuki Yshikawa

Department of Mechanical System Engineering, Kumamoto University, Kumamoto, Japan.
Graduate School of Science and Technology, Kumamoto University, Kumamoto, Japan.
Tokyo Electron Kyushu Ltd., Koshi, Japan.

DOI: 10.4236/ojfd.2013.32A004                

Abstract

Effects of disk edge profile on scattering characteristics of liquid droplets splashed from a rotating disk edge are experimentally investigated. In the present research, aluminum disks are utilized and purified water is employed for liquid. Scattering phenomena of the droplets are captured by the high-speed digital camera. Distribution of the droplet diameter is evaluated from these images and distributions of horizontal flying velocity component and angle of the droplets are measured by human visual observation of images. Liquid filaments are stretched outward from the stagnant liquid layer on lateral surface of disk edge by centrifugal force. Two main peaks appear in the distribution of the scattered droplet diameter and they are originated from large terminal droplets and small droplets generated from filamentwise breakup. Most of the scattered droplets fly slightly inside of the tangential direction of the disk edge. The water droplets splashed from the disk scatters with regularity compared with ethanol droplets.

Keywords

Scattering Droplet; Spinning Disk; Disk Edge Profile; Visualization

Conflicts of Interest

The authors declare no conflicts of interest.

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