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arXiv · 1903.01264

Electroosmotic flow dipole: experimental observation and flow field patterning

Federico Paratore·Evgeniy Boyko·Govind V. Kaigala·Moran Bercovici
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Abstract

We experimentally demonstrate the phenomenon of electroosmotic dipole flow that occurs around a localized surface charge region under the application of an external electric field in a Hele-Shaw cell. We use localized deposition of polyelectrolytes to create well-controlled surface charge variations, and show that for a disk-shaped spot, the internal pressure distribution that arises, results in uniform flow within the spot and dipole flow around it. We further demonstrate the superposition of surface charge spots to create complex flow patterns, without the use of physical walls.

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Federico Paratore, Evgeniy Boyko, Govind V. Kaigala, Moran Bercovici. 2019-02-27. Electroosmotic flow dipole: experimental observation and flow field patterning. https://doi.org/10.1103/physrevlett.122.224502

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