Thermal singularity and droplet motion in one-component fluids on solid substrates with thermal gradients

Handle URI:
http://hdl.handle.net/10754/552870
Title:
Thermal singularity and droplet motion in one-component fluids on solid substrates with thermal gradients
Authors:
Xu, Xinpeng; Qian, Tiezheng
Abstract:
Using a continuum model capable of describing the one-component liquid-gas hydrodynamics down to the contact line scale, we carry out numerical simulation and physical analysis for the droplet motion driven by thermal singularity. For liquid droplets in one-component fluids on heated or cooled substrates, the liquid-gas interface is nearly isothermal. Consequently, a thermal singularity occurs at the contact line and the Marangoni effect due to temperature gradient is suppressed. Through evaporation or condensation in the vicinity of the contact line, the thermal singularity makes the contact angle increase with the increasing substrate temperature. This effect on the contact angle can be used to move the droplets on substrates with thermal gradients. Our numerical results for this kind of droplet motion are explained by a simple fluid dynamical model at the droplet length scale. Since the mechanism for droplet motion is based on the change of contact angle, a separation of length scales is exhibited through a comparison between the droplet motion induced by a wettability gradient and that by a thermal gradient. It is shown that the flow field at the droplet length scale is independent of the statics or dynamics at the contact line scale.
Citation:
Thermal singularity and droplet motion in one-component fluids on solid substrates with thermal gradients 2012, 85 (6) Physical Review E
Publisher:
American Physical Society (APS)
Journal:
Physical Review E
Issue Date:
26-Jun-2012
DOI:
10.1103/PhysRevE.85.061603
Type:
Article
ISSN:
1539-3755; 1550-2376
Additional Links:
http://link.aps.org/doi/10.1103/PhysRevE.85.061603
Appears in Collections:
Publications Acknowledging KAUST Support

Full metadata record

DC FieldValue Language
dc.contributor.authorXu, Xinpengen
dc.contributor.authorQian, Tiezhengen
dc.date.accessioned2015-05-14T12:41:32Zen
dc.date.available2015-05-14T12:41:32Zen
dc.date.issued2012-06-26en
dc.identifier.citationThermal singularity and droplet motion in one-component fluids on solid substrates with thermal gradients 2012, 85 (6) Physical Review Een
dc.identifier.issn1539-3755en
dc.identifier.issn1550-2376en
dc.identifier.doi10.1103/PhysRevE.85.061603en
dc.identifier.urihttp://hdl.handle.net/10754/552870en
dc.description.abstractUsing a continuum model capable of describing the one-component liquid-gas hydrodynamics down to the contact line scale, we carry out numerical simulation and physical analysis for the droplet motion driven by thermal singularity. For liquid droplets in one-component fluids on heated or cooled substrates, the liquid-gas interface is nearly isothermal. Consequently, a thermal singularity occurs at the contact line and the Marangoni effect due to temperature gradient is suppressed. Through evaporation or condensation in the vicinity of the contact line, the thermal singularity makes the contact angle increase with the increasing substrate temperature. This effect on the contact angle can be used to move the droplets on substrates with thermal gradients. Our numerical results for this kind of droplet motion are explained by a simple fluid dynamical model at the droplet length scale. Since the mechanism for droplet motion is based on the change of contact angle, a separation of length scales is exhibited through a comparison between the droplet motion induced by a wettability gradient and that by a thermal gradient. It is shown that the flow field at the droplet length scale is independent of the statics or dynamics at the contact line scale.en
dc.publisherAmerican Physical Society (APS)en
dc.relation.urlhttp://link.aps.org/doi/10.1103/PhysRevE.85.061603en
dc.rightsArchived with thanks to Physical Review Een
dc.titleThermal singularity and droplet motion in one-component fluids on solid substrates with thermal gradientsen
dc.typeArticleen
dc.identifier.journalPhysical Review Een
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionNano Science and Technology (NSNT) Program, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kongen
dc.contributor.institutionDepartment of Mathematics, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kongen
kaust.authorQian, Tiezhengen
kaust.grant.fundedcenterKAUST-HKUST Micro/Nanofluidic Joint Laboratoryen
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