摘要
采用实验方法研究了气-液复合液滴撞击超疏水表面的动力学过程,考察了撞击过程中复合液滴内部空腔破裂的临界条件,及其铺展系数最大值和动态变化的特性,并分析了其与单相液滴撞击现象的区别。实验结果表明:发生空腔破裂的临界阈值随液体黏度的增加和气-液直径比的减小而增加。最大铺展系数随液体黏度和空腔尺寸的增加而减小,推导出了复合液滴空腔破裂临界阈值的理论公式,以及适用于气-液复合液滴最大铺展系数的理论模型。此外也研究了复合液滴撞击后的接触时间,发现在3种气-液直径比下,复合液滴的接触时间均小于单相液滴,并提出了无量纲接触时间随直径比变化的理论公式。
The hydrodynamics of air-liquid compound droplet impact on the super-hydrophobic surface was experimentally studied.We investigated the critical conditions of cavity rupture,the maximum spreading coefficient,and the temporal evolution of the spreading coefficient during impact.The difference between the compound and single-phase droplet impact was analyzed.The experimental results show that the critical threshold of cavity rupture increases with the increase of liquid viscosity and the decrease of air-liquid diameter ratio.The maximum spreading coefficient of compound droplets decreases with the increase of both liquid viscosity and cavity size.We derived the theoretical formula for the critical condition of cavity rupture,and the theoretical model of maximum spreading coefficient for the air-liquid compound droplet impact.In addition,we also studied the contact time of compound droplets after impact,which is smaller than that of the single-phase droplet under three kinds of air-liquid diameter ratio.A theoretical formula of dimensionless contact time with diameter ratio is proposed.
作者
姚程炜
田远思
李二强
YAO Chengwei;TIAN Yuansi;LI Erqiang(School of Engineering Science,University of Science and Technology of China,230026 Hefei,China;School of Construction Machinery,Chang'an University,710064 Xi'an,China)
出处
《应用力学学报》
CAS
CSCD
北大核心
2024年第3期698-707,共10页
Chinese Journal of Applied Mechanics
基金
国家自然科学基金资助项目(No.11972339
11772327)。
关键词
气-液复合液滴
超疏水表面
铺展系数
接触时间
air-liquid compound droplet
super-hydrophobic surface
spreading coefficient
contact time
