Antibubbles and fine cylindrical sheets of air

Handle URI:
http://hdl.handle.net/10754/574978
Title:
Antibubbles and fine cylindrical sheets of air
Authors:
Beilharz, D.; Guyon, A.; Li, E. Q.; Thoraval, M.-J. ( 0000-0002-6590-0603 ) ; Thoroddsen, Sigurdur T. ( 0000-0001-6997-4311 )
Abstract:
Drops impacting at low velocities onto a pool surface can stretch out thin hemispherical sheets of air between the drop and the pool. These air sheets can remain intact until they reach submicron thicknesses, at which point they rupture to form a myriad of microbubbles. By impacting a higher-viscosity drop onto a lower-viscosity pool, we have explored new geometries of such air films. In this way we are able to maintain stable air layers which can wrap around the entire drop to form repeatable antibubbles, i.e. spherical air layers bounded by inner and outer liquid masses. Furthermore, for the most viscous drops they enter the pool trailing a viscous thread reaching all the way to the pinch-off nozzle. The air sheet can also wrap around this thread and remain stable over an extended period of time to form a cylindrical air sheet. We study the parameter regime where these structures appear and their subsequent breakup. The stability of these thin cylindrical air sheets is inconsistent with inviscid stability theory, suggesting stabilization by lubrication forces within the submicron air layer. We use interferometry to measure the air-layer thickness versus depth along the cylindrical air sheet and around the drop. The air film is thickest above the equator of the drop, but thinner below the drop and up along the air cylinder. Based on microbubble volumes, the thickness of the cylindrical air layer becomes less than 100 nm before it ruptures.
KAUST Department:
Physical Sciences and Engineering (PSE) Division; Clean Combustion Research Center
Citation:
Antibubbles and fine cylindrical sheets of air 2015, 779:87 Journal of Fluid Mechanics
Publisher:
Cambridge University Press (CUP)
Journal:
Journal of Fluid Mechanics
Issue Date:
14-Aug-2015
DOI:
10.1017/jfm.2015.335
Type:
Article
ISSN:
0022-1120; 1469-7645
Additional Links:
http://www.journals.cambridge.org/abstract_S0022112015003353
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division; Clean Combustion Research Center

Full metadata record

DC FieldValue Language
dc.contributor.authorBeilharz, D.en
dc.contributor.authorGuyon, A.en
dc.contributor.authorLi, E. Q.en
dc.contributor.authorThoraval, M.-J.en
dc.contributor.authorThoroddsen, Sigurdur T.en
dc.date.accessioned2015-08-18T08:36:17Zen
dc.date.available2015-08-18T08:36:17Zen
dc.date.issued2015-08-14en
dc.identifier.citationAntibubbles and fine cylindrical sheets of air 2015, 779:87 Journal of Fluid Mechanicsen
dc.identifier.issn0022-1120en
dc.identifier.issn1469-7645en
dc.identifier.doi10.1017/jfm.2015.335en
dc.identifier.urihttp://hdl.handle.net/10754/574978en
dc.description.abstractDrops impacting at low velocities onto a pool surface can stretch out thin hemispherical sheets of air between the drop and the pool. These air sheets can remain intact until they reach submicron thicknesses, at which point they rupture to form a myriad of microbubbles. By impacting a higher-viscosity drop onto a lower-viscosity pool, we have explored new geometries of such air films. In this way we are able to maintain stable air layers which can wrap around the entire drop to form repeatable antibubbles, i.e. spherical air layers bounded by inner and outer liquid masses. Furthermore, for the most viscous drops they enter the pool trailing a viscous thread reaching all the way to the pinch-off nozzle. The air sheet can also wrap around this thread and remain stable over an extended period of time to form a cylindrical air sheet. We study the parameter regime where these structures appear and their subsequent breakup. The stability of these thin cylindrical air sheets is inconsistent with inviscid stability theory, suggesting stabilization by lubrication forces within the submicron air layer. We use interferometry to measure the air-layer thickness versus depth along the cylindrical air sheet and around the drop. The air film is thickest above the equator of the drop, but thinner below the drop and up along the air cylinder. Based on microbubble volumes, the thickness of the cylindrical air layer becomes less than 100 nm before it ruptures.en
dc.language.isoenen
dc.publisherCambridge University Press (CUP)en
dc.relation.urlhttp://www.journals.cambridge.org/abstract_S0022112015003353en
dc.rightsThis is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited.en
dc.subjectbreakup/coalescenceen
dc.subjectbubble dynamicsen
dc.subjectdrops and bubblesen
dc.titleAntibubbles and fine cylindrical sheets of airen
dc.typeArticleen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.contributor.departmentClean Combustion Research Centeren
dc.identifier.journalJournal of Fluid Mechanicsen
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionDépartement de Mécanique, Ecole Polytechnique, 91128 Palaiseau CEDEX, Franceen
dc.contributor.institutionPhysics of Fluids Group, Faculty of Science and Technology, MESA+ Institute, University of Twente, 7500 AE Enschede, The Netherlandsen
dc.contributor.affiliationKing Abdullah University of Science and Technology (KAUST)en
kaust.authorThoraval, Marie-Jeanen
kaust.authorThoroddsen, Sigurdur T.en
kaust.authorLi, Erqiangen
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