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Author Ahmadi, A. ♦ McDermid, C. M. ♦ Markley, L.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS ♦ DIELECTRIC MATERIALS ♦ DROPLETS ♦ ELECTRIC POTENTIAL ♦ ELECTRODES ♦ ELECTROLYSIS ♦ GEOMETRY ♦ MAGNETIC FIELDS ♦ PERMANENT MAGNETS
Abstract In this work, a magnetohydrodynamic method is proposed for the actuation of droplets in small-scale planar fluidic systems, providing an alternative to commonly used methods such as electrowetting-on-dielectric. Elementary droplet-based operations, including transport, merging, and mixing, are demonstrated. The forces acting on millimetric droplets are carefully investigated, with a primary focus on the magnetic actuation force and on the unbalanced capillary forces that arise due to hysteresis. A super-hydrophobic channel is 3D printed to guide the droplets, with thin wires installed as contact electrodes and permanent magnets providing a static magnetic field. It is shown that droplet motion is enhanced by increasing the droplet size and minimizing the electrode contact surface. The effects of channel geometry on threshold voltage and minimum moveable droplet volume are characterized. Finally, the presence of electrolysis is investigated and mitigating strategies are discussed.
ISSN 00036951
Educational Use Research
Learning Resource Type Article
Publisher Date 2016-01-04
Publisher Place United States
Journal Applied Physics Letters
Volume Number 108
Issue Number 1


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