# Active Turbulence

@article{Alert2021ActiveT, title={Active Turbulence}, author={Ricard Alert and Jaume Casademunt and Jean François Joanny}, journal={Annual Review of Condensed Matter Physics}, year={2021} }

Active fluids exhibit spontaneous flows with complex spatiotemporal structure, which have been observed in bacterial suspensions, sperm cells, cytoskeletal suspensions, self-propelled colloids, and cell tissues. Despite occurring in the absence of inertia, chaotic active flows are reminiscent of inertial turbulence, and hence they are known as active turbulence. Here, we survey the field, providing a unified perspective over different classes of active turbulence. To this end, we divide our…

## 49 Citations

### Dynamic mode structure of active turbulence

- EngineeringbioRxiv
- 2022

Dense suspensions of swimming bacteria exhibit chaotic flow patterns that promote the mixing and transport of resources and signalling chemicals within cell colonies. While the importance of active…

### Coexistence of Active and Hydrodynamic Turbulence in Two-Dimensional Active Nematics.

- Physics, EngineeringPhysical review letters
- 2022

In active nematic liquid crystals, activity is able to drive chaotic spatiotemporal flows referred to as active turbulence. Active turbulence has been characterized through theoretical and…

### Exact Coherent Structures and Phase Space Geometry of Preturbulent 2D Active Nematic Channel Flow.

- PhysicsPhysical review letters
- 2022

Confined active nematics exhibit rich dynamical behavior, including spontaneous flows, periodic defect dynamics, and chaotic "active turbulence." Here, we study these phenomena using the framework of…

### Mesoscale modeling of active nematics

- Physics
- 2019

Nematic liquid crystals are fluids whose anisotropic molecules have long range orientational order, but no positional order. When the particles are driven by some chemical or biological mechanism,…

### Defect line coarsening and refinement in active nematics

- Materials Science
- 2022

Active matter naturally performs out-of-equilibrium which results in the emergence of diverse dynamic steady-states, including the omnipresent chaotic dynamic state known as active turbulence.…

### Optimal turbulent transport in microswimmer suspensions

- Physics, Environmental SciencePhysical Review Fluids
- 2022

Microswimmer suspensions self-organize into complex spatio-temporal ﬂow patterns, including vortex lattices and mesoscale turbulence. Here we explore the consequences for the motion of passive…

### Fingering instability of active nematic droplets

- PhysicsJournal of Physics A: Mathematical and Theoretical
- 2022

From the mitotic spindle up to tissues and biofilms, many biological systems behave as active droplets, which often break symmetry and change shape spontaneously. Here, I show that active nematic…

### Nematic order condensation and topological defects in inertial active nematics.

- PhysicsPhysical review. E
- 2022

Living materials at different length scales manifest active nematic features such as orientational order, nematic topological defects, and active nematic turbulence. Using numerical simulations we…

### Active particles crossing sharp viscosity gradients

- PhysicsScientific Reports
- 2023

Active particles (living or synthetic) often move through inhomogeneous environments, such as gradients in light, heat or nutrient concentration, that can lead to directed motion (or taxis ). Recent…

### Shapes and dynamic regimes of an active fluid droplet under confinement

- Engineering
- 2022

Active droplets are artiﬁcial microswimmers built from a liquid dispersion by microﬂuidic tools and showing self-propelled motion. These systems hold par-ticular interest for mimicking biological…

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It is shown that the spinners, emerging as a result of spontaneous symmetry breaking of clock/counterclockwise rotation of self-assembled particle chains, generate vigorous vortical flows at the interface, demonstrating the properties of a 2D hydrodynamic turbulence.

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Active turbulence describes a flow regime that is erratic, and yet endowed with a characteristic length scale1. It arises in animate soft-matter systems as diverse as bacterial baths2, cell tissues3…

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Meso-scale turbulence was originally observed experimentally in various suspensions of swimming bacteria, as well as in the collective motion of active colloids. The corresponding large scale…

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