Drops on the Underside of a Slightly Inclined Wet Substrate Move Too Fast to Grow

Autor: Pier Giuseppe Ledda, Etienne Jambon-Puillet, François Gallaire, Pierre-Thomas Brun
Rok vydání: 2021
Předmět:
Zdroj: Physical Review Letters. 127
ISSN: 1079-7114
0031-9007
DOI: 10.1103/physrevlett.127.044503
Popis: Pendant drops suspended on the underside of a wet substrate are known to accumulate fluid from the surrounding thin liquid film, a process that often results in dripping. The growth of such drops is hastened by their ability to translate over an otherwise uniform horizontal film. Here we show that this scenario is surprisingly reversed when the substrate is slightly tilted ($\ensuremath{\approx}2\ifmmode^\circ\else\textdegree\fi{}$); drops become too fast to grow and shrink over the course of their motion. Combining experiments and numerical simulations, we rationalize the transition between the conventional growth regime and the previously unknown decay regime we report. Using an analytical treatment of the Landau-Levich meniscus that connects the drop to the film, we quantitatively predict the drop dynamics in the two flow regimes and the value of the critical inclination angle where the transition between them occurs.
Databáze: OpenAIRE