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arXiv · 1309.2770

Viscous fingering at ultralow interfacial tension

Siti Aminah Setu·Ioannis Zacharoudiou·Gareth J. Davies·Denis Bartolo·Sebastien Moulinet·Ard A. Louis·Julia M. Yeomans·Dirk G. A. L. Aarts
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Abstract

We experimentally study the viscous fingering instability in a fluid-fluid phase separated colloid-polymer mixture by means of laser scanning confocal microscopy and microfluidics. We focus on three aspects of the instability. (i) The interface between the two demixed phases has an ultralow surface tension, such that we can address the role of thermal interface fluctuations. (ii) We image the interface in three dimensions allowing us to study the interplay between interface curvature and flow. (iii) The displacing fluid wets all walls completely, in contrast to traditional viscous fingering experiments, in which the displaced fluid wets the walls. We also perform lattice Boltzmann simulations, which help to interpret the experimental observations.

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Siti Aminah Setu, Ioannis Zacharoudiou, Gareth J. Davies, Denis Bartolo, Sebastien Moulinet, Ard A. Louis, Julia M. Yeomans, Dirk G. A. L. Aarts. 2013-09-11. Viscous fingering at ultralow interfacial tension. https://doi.org/10.1039/c3sm51571k

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