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

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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Cited by in corpus (17)

• Confinement controlled bend instability of three-dimensional active fluids
• Confinement-induced Self-Pumping in 3D Active Fluids
• Data-driven discovery of active nematic hydrodynamics
• Asymmetric fluctuations and self-folding of active interfaces
• Helical Flow States in Active Nematics
• Spontaneous flow instabilities of active polar fluids in three dimensions
• Defect Loops in Three-Dimensional Active Nematics as Active Multipoles
• Defect dynamics in active smectics induced by confining geometry and topology
• Vortex Lattices in Active Nematics with Periodic Obstacle Arrays
• Vorticity phase separation and defect lattices in the isotropic phase of active liquid crystals
• Friction mediated phase transition in confined active nematics
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• Boundaries control active channel flows
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• Nematronics: Reciprocal coupling between ionic currents and nematic dynamics
• Active nematics in corrugated channels
• Active nematic flows confined in a two dimensional channel with hybrid alignment at the walls: a unified picture