THERMAL SCIENCE

International Scientific Journal

Fang-Fang Li

,

Chen Huang

,

En Xie

,

Guang-Qiang Wang

,

Jun Qiu

MICROSCOPIC EXPERIMENTAL STUDY ON ACOUSTIC AGGLOMERATION OF THE DROPLETS ON WALL

ABSTRACT
Study on the effect of acoustic wave on droplet collision-coalescence process is interesting and helps to better understand the acoustic agglomeration mechanism. This study designs and carries out a microscopic experiment to investigate the effect of acoustic wave on wall droplet collision-coalescence process. The derived microscopic images of droplets under the action of different sound waves at different moment are processed and analyzed by binaryzation with iterative threshold, cavity filling, morphological open arithmetic processing, and identification of connected regions, etc. Using a newly defined parameter, equivalent droplet size, the growth rates of the droplets in natural state and under the action of different acoustic parameters are compared and analyzed. The results show that the effect of sound wave greatly accelerates the collision-coalescence process of the droplet, and comparing with sound pressure level, the frequency of the sound wave is a more effective parameter in promoting the collision-coalescence process of wall droplets, and the lower the acoustic wave frequency results in larger collision-coalescence rate.
KEYWORDS
acoustic agglomeration, acoustic frequency, sound pressure level, droplet collision-coalescence process, microscopic image processing
PAPER SUBMITTED: 2020-03-09
PAPER REVISED: 1970-01-01
PAPER ACCEPTED: 2020-08-16
PUBLISHED ONLINE: 2020-09-06
DOI REFERENCE: https://doi.org/10.2298/TSCI200309233L
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2021, VOLUME 25, ISSUE Issue 5, PAGES [3899 - 3910]
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Microscopic experimental study on acoustic agglomeration of the droplets on wall

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence