Extraordinarily Rapid Rise of Tiny Bubbles Sliding beneath Superhydrophobic Surfaces
Tiny bubbles readily stick onto substrates owing to contact angle hysteresis (CAH). Nevertheless, they can slide slowly on a tilted surface with ultralow CAH because capillarity is overcome by buoyancy. It is surprising to observe experimentally that bubbles of 3-15 μL (diameter 1.79-3.06 mm) slide...
| Publié dans: | Langmuir : the ACS journal of surfaces and colloids. - 1985. - 33(2017), 5 vom: 07. Feb., Seite 1326-1331 |
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| Auteur principal: | |
| Autres auteurs: | , , |
| Format: | Article en ligne |
| Langue: | English |
| Publié: |
2017
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| Accès à la collection: | Langmuir : the ACS journal of surfaces and colloids |
| Sujets: | Journal Article Research Support, Non-U.S. Gov't |
| Résumé: | Tiny bubbles readily stick onto substrates owing to contact angle hysteresis (CAH). Nevertheless, they can slide slowly on a tilted surface with ultralow CAH because capillarity is overcome by buoyancy. It is surprising to observe experimentally that bubbles of 3-15 μL (diameter 1.79-3.06 mm) slide beneath a tilted superhydrophobic surface at a vertical ascent rate faster than that of freely rising ones of high Reynold numbers ≈O(102). As the tilting angle increases, the drag coefficient remains essentially the same as that of a freely rising bubble, but the frontal area of the flat bubble rises monotonically. Nonetheless, the frontal area of the sliding bubble always stays much smaller than that of a freely rising bubble. Consequently, the small drag force associated with the sliding bubbles is attributed to their substantially small frontal areas on superhydrophobic surfaces |
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| Description: | Date Completed 18.04.2018 Date Revised 18.04.2018 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 1520-5827 |
| DOI: | 10.1021/acs.langmuir.6b04645 |