Influence of wavy-structured superhydrophobic surfaces on coalescence-induced droplet jumping

被引：0
|
作者：
Li Y. [1 ]
Li Q. [1 ]
Wang H. [1 ,2 ]
Zhu X. [1 ,2 ]
Chen R. [1 ,2 ]
Liao Q. [1 ,2 ]
Ding Y. [1 ,2 ]
机构：
[1] Institute of Engineering Thermophysics, Chongqing University, Chongqing
[2] Key Laboratory of Low-Grade Energy Utilization Technologies and Systems, Ministry of Education, Chongqing University, Chongqing
来源：
Huagong Xuebao/CIESC Journal | 2022年 / 73卷 / 10期
关键词：
droplets jumping; horizontal motion; interfacial tension; numerical simulation; superhydrophobic surface; two-phase flow;
D O I：
10.11949/0438-1157.20220680
中图分类号：
学科分类号：
摘要：
Spontaneous coalescence of droplets is widespread in nature and industry. How to efficiently remove coalesced droplets is an important part of strengthening droplet condensation heat transfer and preventing icing. In this paper, the coalescence-induced droplet jumping with different radius ratios on superhydrophobic horizontal wall and superhydrophobic wavy wall is studied by numerical simulation. The horizontal and vertical velocities of the droplets coalescing on the flat wall surface differ by 1—2 orders of magnitude, the horizontal displacement of the droplets is small, so it's difficult to remove them effectively after coalescing. However, on the wavy wall surface, because the liquid bridge impinges on the inclined surface, the droplet is subjected to a large horizontal component force, and the horizontal velocity of the droplet remains at the same order of magnitude as the vertical velocity after coalescence, and the horizontal displacement increases significantly. Moreover, the wave structure has a significant effect. With the increase of the wave aspect ratio, the horizontal displacement of the droplet increases and the bounce height decreases, which can effectively promote the horizontal movement of the droplet. When the aspect ratio is 0.21, the promotion effect is close to the peak value. The findings provide a new reference for the efficient removal of coalesced droplets. © 2022 Chemical Industry Press. All rights reserved.
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页码：4345 / 4354
页数：9
相关论文
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