Stretching water between two grooves

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Leonard, Matteo, Maity, Dilip, Vandewalle, Nicolas, Truscott, Tadd
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866916979403653120
author Leonard, Matteo
Maity, Dilip
Vandewalle, Nicolas
Truscott, Tadd
author_facet Leonard, Matteo
Maity, Dilip
Vandewalle, Nicolas
Truscott, Tadd
contents Controlling water motion on surfaces is critical for applications ranging from thermal management, passive water harvesting, to self-cleaning coatings. Yet stabilising continuous water films, desirable for their high surface coverage and drainage capacity, remains challenging with pure water, due to its high surface tension. Existing strategies rely on extreme wettability achieved by coating or fine-scale patterning, which are costly, fragile, or complex to scale. A robust, purely geometric solution is still lacking. We demonstrate that a pair of laser-engraved grooves on a moderately hydrophilic vertical substrate can laterally anchor water and stretch a continuous thin film, without any other surface treatment. Once stabilised, the film extends vertically over 100 capillary lengths (> 30cm), with thickness tunable via both flow rate and groove geometry. At the groove extremities, the end of anchoring triggers a cyclic instability, characterised by film rupture, retraction, and droplet release. The thickness of the film and retraction height obey predictive models, while droplet mass varies systematically with spacing and surface tension. This groove-based method offers a straightforward and scalable approach to creating, sustaining, and controlling thin water films. It opens new directions for passive liquid control in condensation, surface cleaning, and 2D millifluidic systems.
format Preprint
id arxiv_https___arxiv_org_abs_2509_25864
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Stretching water between two grooves
Leonard, Matteo
Maity, Dilip
Vandewalle, Nicolas
Truscott, Tadd
Fluid Dynamics
Controlling water motion on surfaces is critical for applications ranging from thermal management, passive water harvesting, to self-cleaning coatings. Yet stabilising continuous water films, desirable for their high surface coverage and drainage capacity, remains challenging with pure water, due to its high surface tension. Existing strategies rely on extreme wettability achieved by coating or fine-scale patterning, which are costly, fragile, or complex to scale. A robust, purely geometric solution is still lacking. We demonstrate that a pair of laser-engraved grooves on a moderately hydrophilic vertical substrate can laterally anchor water and stretch a continuous thin film, without any other surface treatment. Once stabilised, the film extends vertically over 100 capillary lengths (> 30cm), with thickness tunable via both flow rate and groove geometry. At the groove extremities, the end of anchoring triggers a cyclic instability, characterised by film rupture, retraction, and droplet release. The thickness of the film and retraction height obey predictive models, while droplet mass varies systematically with spacing and surface tension. This groove-based method offers a straightforward and scalable approach to creating, sustaining, and controlling thin water films. It opens new directions for passive liquid control in condensation, surface cleaning, and 2D millifluidic systems.
title Stretching water between two grooves
topic Fluid Dynamics
url https://arxiv.org/abs/2509.25864