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arXiv · 1505.03478

Oscillation and collective conveyor of water-in-oil droplets by microfluidic bolus flow

Takuya Ohmura·Masatoshi Ichikawa·Ken-ichiro Kamei·Yusuke T. Maeda
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Abstract

Microfluidic techniques have been extensively developed to realize micro-total analysis systems in a small chip. For microanalysis, electro-magnetic forces have generally been utilized for the trapping of objects, but hydrodynamics has been little explored despite its relevance to pattern formation. Here, we report that water-in-oil (W/O) droplets can be transported in the grid of an array of other large W/O droplets. As each droplet approaches an interspace of the large droplet array, while exhibiting persistent back-and-forth motion, it is conveyed at a velocity equal to the droplet array. We confirm the appearance of closed streamlines in a numerical simulation, suggesting that a vortex-like stream is involved in trapping the droplet. Furthermore, more than one droplet is also conveyed as an ordered cluster with dynamic reposition.

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Takuya Ohmura, Masatoshi Ichikawa, Ken-ichiro Kamei, Yusuke T. Maeda. 2015-08-05. Oscillation and collective conveyor of water-in-oil droplets by microfluidic bolus flow. https://doi.org/10.1063/1.4928753

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