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Updated: Jul 10, 2025

Fabricating High-viscosity Droplets using Microfluidic Capillary Device with Phase-inversion Co-flow Structure
Published on: April 17, 2018
Thermocapillary Migrating Odd Viscous Droplets
A Aggarwal1, E Kirkinis1, M Olvera de la Cruz1
1Department of Materials Science and Engineering, Robert R. McCormick School of Engineering and Applied Science, Northwestern University, Evanston, Illinois 60208, USA and Center for Computation and Theory of Soft Materials, Northwestern University, Evanston, Illinois 60208, USA.
Abstract:
A droplet of a classical liquid surrounded by a cold gas placed on a hot substrate is accompanied by unremitting internal circulations, while the droplet remains immobile. Two identical cells with opposite sense of circulation form in the interior due to the thermocapillary effect induced by the gas and substrate temperature difference. Under the same conditions, a droplet composed of an odd viscous liquid exerts a compressive stress on the cell rotating in one sense and tensile on the cell rotating in the opposite sense resulting in a tilted droplet configuration. A sufficiently strong thermal gradient leads the contact angles to overcome hysteresis effects and induces droplet migration.
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