Abstract：The purpose of this work is to investigate the liquid ejection process of a micro droplet generator by applying a numerical approach. The time evolution of droplet shape characteristics is predicted. The flow behavior in the liquid ejection and droplet formation processes are examined with water as a baseline test fluid in a full ejection cycle. Numerical experiments are conducted to determine droplet ejection characteristics by systematically varying the velocity period, magnitude and amplitude as well as the contact angle at the nozzle inlet. The uniform and steady droplet formation region is exploited at different inertial proportions. The simulations results reveal that the dimensionless number Re,CH, ZF have a significant influence on the behavior of the droplet ejection characteristics, and the uniform and steady droplets can be formed under certain conditions. A lower velocity of the first droplet can be achieved by reducing the three dimensionless numbers. However, the ejection velocity is too low to form the droplet as Re is smaller than 9. The droplet through a hydrophobic surface breaks up later than one through a hydrophilic surface.
杨敏官, 闫龙龙, 王育立, 龚辰, 陆金刚. 喷嘴入口条件对微液滴生成的影响[J]. 排灌机械工程学报, 2015, 33(3): 226-232.
Yang Minguan, Yan Longlong, Wang Yuli, Gong Chen, Lu Jingang. Effects of nozzle inlet conditions on micro-droplet formation. Journal of Drainage and Irrigation Machinery Engin, 2015, 33(3): 226-232.
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