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arXiv · 2007.05263

Flow states and transitions of an active nematic in a three dimensional channel

Santhan Chandragiri·Amin Doostmohammadi·Julia M. Yeomans·Sumesh P. Thampi
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Abstract

We use active nematohydrodynamics to study the flow of an active fluid in a 3D microchannel, finding a transition between active turbulence and regimes where there is a net flow along the channel. We show that the net flow is only possible if the active nematic is flow aligning and that - in agreement with experiments - the appearance of the net flow depends on the aspect ratio of the channel cross-section. We explain our results in terms of the when hydrodynamic screening due to the channel walls allows the emergence of vortex rolls across the channel.

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Santhan Chandragiri, Amin Doostmohammadi, Julia M. Yeomans, Sumesh P. Thampi. 2020-07-10. Flow states and transitions of an active nematic in a three dimensional channel. https://doi.org/10.1103/physrevlett.125.148002

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