Ricocheting Droplets Moving on Super‐Repellent Surfaces

Advanced Science

Mattias Björnmalm¹  Frank Caruso¹  Qi‐Zhi Zhong¹  Zhixing Lin¹  Joseph J. Richardson¹  Jiajing Zhou¹  Jianhua Li¹  Gyeongwon Yun¹  Quinn A. Besford¹  Zhichao Dong²  Lei Jiang²  Qiang Sun³  Joseph D. Berry³  Shuaijun Pan⁴  Yanbing Lu⁴  Weijian Xu⁴  Rui Guo⁴  Jianhui Jiang⁴  Margaret Katherine Banks⁵  Ruoxi Wu⁵ 

[1] ARC Centre of Excellence in Convergent Bio‐Nano Science and Technology, and the Department of Chemical Engineering The University of Melbourne Parkville Victoria 3010 Australia;CAS Key Laboratory of Bio‐inspired Materials and Interfacial Sciences Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 China;Department of Chemical Engineering and the Particulate Fluids Processing Centre The University of Melbourne Parkville Victoria 3010 Australia;State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China;Zachry Department of Civil Engineering Texas A&M University 3136 TAMU College Station TX 77843‐3136 USA;

关键词: contact time;    droplet bouncing;    interfacial phenomena;    repellent coatings;    surface science;   

DOI  :  10.1002/advs.201901846

来源: DOAJ

【 摘 要 】

Abstract Droplet bouncing on repellent solid surfaces (e.g., the lotus leaf effect) is a common phenomenon that has aroused interest in various fields. However, the scenario of a droplet bouncing off another droplet (either identical or distinct chemical composition) while moving on a solid material (i.e., ricocheting droplets, droplet billiards) is scarcely investigated, despite it having fundamental implications in applications including self‐cleaning, fluid transport, and heat and mass transfer. Here, the dynamics of bouncing collisions between liquid droplets are investigated using a friction‐free platform that ensures ultrahigh locomotion for a wide range of probing liquids. A general prediction on bouncing droplet–droplet contact time is elucidated and bouncing droplet–droplet collision is demonstrated to be an extreme case of droplet bouncing on surfaces. Moreover, the maximum deformation and contact time are highly dependent on the position where the collision occurs (i.e., head‐on or off‐center collisions), which can now be predicted using parameters (i.e., effective velocity, effective diameter) through the concept of an effective interaction region. The results have potential applications in fields ranging from microfluidics to repellent coatings.

【 授权许可】

Unknown