Bouncing microdroplets on hydrophobic surfaces

• 成果类型: Article
• 署名作者: McLauchlan, Jamie; Walker, Jim S.; Sanjay, Vatsal; Jalaal, Maziyar; Reid, Jonathan P.; Squires, Adam M.; Souslov, Anton
• 署名单位: University of Bath; University of Bristol; Durham University; University of Amsterdam; University of Bath; University of Cambridge
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-10973
• DOI: 10.1073/pnas.2507309122
• 发表日期: 2025-09-09
• 关键词: drop impact; DYNAMICS; simulations; outcomes; MODEL

摘要

Intuitively, slow droplets stick to a surface and faster droplets splash or bounce. However, recent work suggests that on nonwetting surfaces, whether microdroplets stick or bounce depends only on their size and fluid properties, but not on the incoming velocity. Here, we show using theory and experiments that even poorly wetting surfaces have a velocity-dependent criterion for bouncing of aqueous droplets, which is as high as 6 m/s for diameters of 30 to 50 mu m on hydrophobic surfaces such as Teflon. We quantify this criterion by analyzing the interplay of dissipation, surface adhesion, and incoming kinetic energy, and describe a wealth of associated phenomena, including air bubbles and satellite droplets. Our results on inertial microdroplets elucidate fundamental processes crucial to aerosol science and technology.