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arXiv · 1109.1732

Characteristic spatial scale of vesicle pair interactions in a plane linear flow

Michael Levant·Julien Deschamps·Eldad Afik·Victor Steinberg
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Abstract

We report the experimental studies on interaction of two vesicles trapped in a microfluidic analog of four-roll mill, where a plane linear flow is realized. We found that the dynamics of a single vesicle is significantly altered by the presence of another vesicle at separation distances up to about 3.2 ÷3.7 times of effective radius of the vesicles. This is supported by direct measurements of a single vesicle back-reaction on the velocity field. Thus, the experiment provides the lower bound for the interaction scale of vesicles and so the corresponding upper bound for the volume fraction ϕ=0.08 ÷0.13 of non-interacting vesicle suspensions.

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Michael Levant, Julien Deschamps, Eldad Afik, Victor Steinberg. 2012-04-30. Characteristic spatial scale of vesicle pair interactions in a plane linear flow. https://doi.org/10.1103/physreve.85.056306

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