The fastest drop climbing on a wet conical fibre

Handle URI:
http://hdl.handle.net/10754/552102
Title:
The fastest drop climbing on a wet conical fibre
Authors:
Li, Erqiang ( 0000-0002-5003-0756 ) ; Thoroddsen, Sigurdur T. ( 0000-0001-6997-4311 )
Abstract:
We use high-speed video imaging to study the capillary-driven motion of a micro-droplet along the outside of a pre-wetted conical fiber. The cones are fabricated on a glass-puller with tip diameters as small as 1 μm, an order of magnitude smaller than in previous studies. The liquid is fed through the hollow fiber accumulating at the fiber tip to form droplets. The droplets are initially attached to the opening as they grow in size before detaching and traveling up the cone. This detachment can produce a transient oscillation of high frequency. The spatial variation of the capillary pressure drives the droplets towards the wider side of the cone. Various liquids were used to change the surface tension by a factor of 3.5 and viscosity by a factor of 1500. Within each droplet size and viscous-dissipation regime, the data for climbing speeds collapse on a single curve. Droplets traveling with and against gravity allow us to pinpoint the absolute strength of the driving capillary pressure and viscous stresses and thereby determine the prefactors in the dimensionless relationships. The motions are consistent with earlier results obtained from much larger cones. Translation velocities up to 270 mm/s were observed and overall the velocities follow capillary-viscous scaling, whereas the speed of the fastest droplets is limited by inertia following their emergence at the cone tip.
KAUST Department:
Clean Combustion Research Center; Physical Sciences and Engineering (PSE) Division
Citation:
The fastest drop climbing on a wet conical fibre 2013, 25 (5):052105 Physics of Fluids
Publisher:
AIP Publishing
Journal:
Physics of Fluids
Issue Date:
21-May-2013
DOI:
10.1063/1.4805068
Type:
Article
ISSN:
10706631
Additional Links:
http://scitation.aip.org/content/aip/journal/pof2/25/5/10.1063/1.4805068
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division; Clean Combustion Research Center

Full metadata record

DC FieldValue Language
dc.contributor.authorLi, Erqiangen
dc.contributor.authorThoroddsen, Sigurdur T.en
dc.date.accessioned2015-05-03T13:58:43Zen
dc.date.available2015-05-03T13:58:43Zen
dc.date.issued2013-05-21en
dc.identifier.citationThe fastest drop climbing on a wet conical fibre 2013, 25 (5):052105 Physics of Fluidsen
dc.identifier.issn10706631en
dc.identifier.doi10.1063/1.4805068en
dc.identifier.urihttp://hdl.handle.net/10754/552102en
dc.description.abstractWe use high-speed video imaging to study the capillary-driven motion of a micro-droplet along the outside of a pre-wetted conical fiber. The cones are fabricated on a glass-puller with tip diameters as small as 1 μm, an order of magnitude smaller than in previous studies. The liquid is fed through the hollow fiber accumulating at the fiber tip to form droplets. The droplets are initially attached to the opening as they grow in size before detaching and traveling up the cone. This detachment can produce a transient oscillation of high frequency. The spatial variation of the capillary pressure drives the droplets towards the wider side of the cone. Various liquids were used to change the surface tension by a factor of 3.5 and viscosity by a factor of 1500. Within each droplet size and viscous-dissipation regime, the data for climbing speeds collapse on a single curve. Droplets traveling with and against gravity allow us to pinpoint the absolute strength of the driving capillary pressure and viscous stresses and thereby determine the prefactors in the dimensionless relationships. The motions are consistent with earlier results obtained from much larger cones. Translation velocities up to 270 mm/s were observed and overall the velocities follow capillary-viscous scaling, whereas the speed of the fastest droplets is limited by inertia following their emergence at the cone tip.en
dc.publisherAIP Publishingen
dc.relation.urlhttp://scitation.aip.org/content/aip/journal/pof2/25/5/10.1063/1.4805068en
dc.rightsArchived with thanks to Physics of Fluids. © 2013 AIP Publishing LLCen
dc.titleThe fastest drop climbing on a wet conical fibreen
dc.typeArticleen
dc.contributor.departmentClean Combustion Research Centeren
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalPhysics of Fluidsen
dc.eprint.versionPublisher's Version/PDFen
kaust.authorLi, Erqiangen
kaust.authorThoroddsen, Sigurdur T.en
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