中国物理B ›› 2016, Vol. 25 ›› Issue (10): 108202-108202.doi: 10.1088/1674-1056/25/10/108202

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Hydrodynamics of passing-over motion during binary droplet collision in shear flow

Cheng-Yao Wang(王程遥), Cheng-Bin Zhang(张程宾), Xiang-Yong Huang(黄庠永), Xiang-Dong Liu(刘向东), Yong-Ping Chen(陈永平)   

  1. 1 Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China;
    2 School of Hydraulic, Energy and Power Engineering, Yangzhou University, Yangzhou 225127, China
  • 收稿日期:2016-05-14 修回日期:2016-07-02 出版日期:2016-10-05 发布日期:2016-10-05
  • 通讯作者: Yong-Ping Chen E-mail:ypchen@seu.edu.cn
  • 基金资助:
    Project supported by the NSAF (Grants No. U1530260), the National Natural Science Foundation of China (Grant No. 51306158), the Natural Science Foundation of Jiangsu Province, China (Grant No. BK20130621), and the Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund (the second phase).

Hydrodynamics of passing-over motion during binary droplet collision in shear flow

Cheng-Yao Wang(王程遥)1, Cheng-Bin Zhang(张程宾)1, Xiang-Yong Huang(黄庠永)2, Xiang-Dong Liu(刘向东)2, Yong-Ping Chen(陈永平)1,2   

  1. 1 Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China;
    2 School of Hydraulic, Energy and Power Engineering, Yangzhou University, Yangzhou 225127, China
  • Received:2016-05-14 Revised:2016-07-02 Online:2016-10-05 Published:2016-10-05
  • Contact: Yong-Ping Chen E-mail:ypchen@seu.edu.cn
  • Supported by:
    Project supported by the NSAF (Grants No. U1530260), the National Natural Science Foundation of China (Grant No. 51306158), the Natural Science Foundation of Jiangsu Province, China (Grant No. BK20130621), and the Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund (the second phase).

摘要: A combined experimental and numerical study is undertaken to investigate the hydrodynamic characteristics of single-phase droplet collision in a shear flow. The passing-over motion of interactive droplets is observed, and the underlying hydrodynamic mechanisms are elucidated by the analysis of the motion trajectory, transient droplet deformation and detailed hydrodynamic information (e.g., pressure and flow fields). The results indicate that the hydrodynamic interaction process under shear could be divided into three stages: approaching, colliding, and separating. With the increasing confinement, the interaction time for the passing-over process is shorter and the droplet processes one higher curvature tip and more stretched profile. Furthermore, the lateral separation Δy/R1 exhibits larger decrease in the approaching stage and the thickness of the lubrication film is decreased during the interaction. As the initial lateral separation increases, the maximum trajectory shift by the collision interaction is getting smaller. During the collision between two droplets with different sizes, the amplitude of the deformation oscillation of the larger droplet is decreased by reducing the size ratio of the smaller droplet to the bigger one.

关键词: droplet collision, passing-over motion, hydrodynamics, shear flow

Abstract: A combined experimental and numerical study is undertaken to investigate the hydrodynamic characteristics of single-phase droplet collision in a shear flow. The passing-over motion of interactive droplets is observed, and the underlying hydrodynamic mechanisms are elucidated by the analysis of the motion trajectory, transient droplet deformation and detailed hydrodynamic information (e.g., pressure and flow fields). The results indicate that the hydrodynamic interaction process under shear could be divided into three stages: approaching, colliding, and separating. With the increasing confinement, the interaction time for the passing-over process is shorter and the droplet processes one higher curvature tip and more stretched profile. Furthermore, the lateral separation Δy/R1 exhibits larger decrease in the approaching stage and the thickness of the lubrication film is decreased during the interaction. As the initial lateral separation increases, the maximum trajectory shift by the collision interaction is getting smaller. During the collision between two droplets with different sizes, the amplitude of the deformation oscillation of the larger droplet is decreased by reducing the size ratio of the smaller droplet to the bigger one.

Key words: droplet collision, passing-over motion, hydrodynamics, shear flow

中图分类号:  (Emulsions and suspensions)

  • 82.70.Kj
83.50.-v (Deformation and flow ?) 47.61.Jd (Multiphase flows) 68.05.-n (Liquid-liquid interfaces)