https://doi.org/10.1140/epjs/s11734-024-01119-0
Regular Article
Experimental and numerical study of the evaporation of a pure water drop on a salt surface
1
Institut Lumière Matière, Université Claude Bernard Lyon 1, CNRS UMR 5306, Campus de la Doua, 69622, Villeurbanne, France
2
Laboratory of mathematical modeling, Astrakhan Tatishchev State University, 414056, Astrakhan, Russia
e
jean.colombani@univ-lyon1.fr
Received:
17
November
2023
Accepted:
12
February
2024
Published online:
21
February
2024
When a pure water drop evaporates on a salt substrate, it experiences the simultaneous dissolution of the solid, evaporation of the liquid, advection of the dissolved species, and nucleation and growth of a salt deposit in the constrained geometry of the pinned drop. This complex configuration induces two original behaviors compared to other drop desiccation situations. First the initial flow inside the drop is a solutal Marangoni loop, due to the vertical concentration gradient stemming from the salt dissolution. Then a centrifugal coffee-stain-type flow progressively replaces this loop, owing to the homogenization of the concentration. The transition from the first to the second flow pattern proceeds via a circular stagnation line migrating centripetally. Secondly, the final deposit is a thin shell forming either inclined walls or a hollow circular rim, an uncommon morphology of stain. We show here that these features are robust, being obtained in a wide range of drop radius, contact angle, temperature, and relative humidity.
Copyright comment Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
© The Author(s), under exclusive licence to EDP Sciences, Springer-Verlag GmbH Germany, part of Springer Nature 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
