Electroosmotic flow dipole: experimental observation and flow field patterning

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.

Manuscript 9 pages, 5 figures; Supplementary Material 9 pages, 2 supplementary figures

References in corpus (1)

• Convection-Enhanced Biopatterning with Recirculation of Hydrodynamically Confined Nanoliter Volumes of Reagents

Cited by in corpus (5)

• Vortices of Electro-osmotic Flow in Heterogeneous Porous Media
• Non-uniform electro-osmotic flow drives fluid-structure instability
• Self-generated electrokinetic flows from active-charged boundary patterns
• An electrokinetic route to giant augmentation in load bearing capacity of compliant microfluidic channels
• Experiments on transformation microfluidics: cloaking flow and transport without metamaterials