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The Effect of Surface Induced Flows on Bubble and Particle AggregationAlmost 20 years have elapsed since a phenomenon called "radial specific coalescence" was identified. During studies of electrolytic oxygen evolution from the back side of a vertically oriented, transparent tin oxide electrode in alkaline electrolyte, one of the authors (Sides) observed that large "collector" bubbles appeared to attract smaller bubbles. The bubbles moved parallel to the surface of the electrode, while the electric field was normal to the electrode surface. The phenomenon was reported but not explained. More recently self ordering of latex particles was observed during electrophoretic deposition at low DC voltages likewise on a transparent tin oxide electrode. As in the bubble work, the field was normal to the electrode while the particles moved parallel to it. Fluid convection caused by surface induced flows (SIF) can explain these two apparently different experimental observations: the aggregation of particles on an electrode during electrophoretic deposition, and a radial bubble coalescence pattern on an electrode during electrolytic gas evolution. An externally imposed driving force (the gradient of electrical potential or temperature), interacting with the surface of particles or bubbles very near a planar conducting surface, drives the convection of fluid that causes particles and bubbles to approach each other on the electrode.
Document ID
20010004346
Acquisition Source
Headquarters
Document Type
Conference Paper
Authors
Guelcher, Scott A.
(Carnegie-Mellon Univ. Pittsburgh, PA United States)
Solomentsev, Yuri E.
(Carnegie-Mellon Univ. Pittsburgh, PA United States)
Anderson, John L.
(Carnegie-Mellon Univ. Pittsburgh, PA United States)
Boehmer, Marcel
(Philips Research Labs. Eindhoven, Netherlands)
Sides, Paul J.
(Carnegie-Mellon Univ. Pittsburgh, PA United States)
Date Acquired
August 20, 2013
Publication Date
March 1, 1999
Publication Information
Publication: Proceedings of the Fourth Microgravity Fluid Physics and Transport Phenomena Conference
Subject Category
Fluid Mechanics And Thermodynamics
Funding Number(s)
CONTRACT_GRANT: NGT5-50054
CONTRACT_GRANT: NSF CTS-94-20780
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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