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… 
[PDF] Semantic Reader
52 Citations
Highly Influential Citations
1
Background Citations
15
Methods Citations
2
Results Citations
1

Figures from this paper

52 Citations

Dynamic mode structure of active turbulence

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.

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.

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

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

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

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

  • Ricard Alert
  • Physics
    Journal 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.

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

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

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…
...

References

SHOWING 1-10 OF 160 REFERENCES

Active turbulence in a gas of self-assembled spinners

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.

Selection mechanism at the onset of active turbulence

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…

Onset of meso-scale turbulence in active nematics

This work shows how the motion of active matter along a micro-channel transitions to meso-scale turbulence through the evolution of locally disordered patches (active puffs) from an ordered vortex-lattice flow state, and demonstrates that the stationary critical exponents of this transition in a channel coincide with the directed percolation universality class.

Taming active turbulence with patterned soft interfaces

Guillamat et al. investigate an active nematic constrained in a quasi-2D geometrical setup and show that there exists an intrinsic length scale that determines the geometry in all forcing regimes.

Motility-induced clustering and meso-scale turbulence in active polar fluids

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…

Condensate formation and multiscale dynamics in two-dimensional active suspensions.

A low-dimensional model is discussed that describes the main features of the transition through nonlocal-in-scale coupling between the small-scale driving and the condensate, formation induced by the classical inverse energy cascade in Newtonian 2D turbulence.

Multi-scale statistics of turbulence motorized by active matter

A number of micro-scale biological flows are characterized by spatio-temporal chaos. These include dense suspensions of swimming bacteria, microtubule bundles driven by motor proteins and dividing…

Universal scaling of active nematic turbulence

A landmark of turbulence is the emergence of universal scaling laws, such as Kolmogorov’s E ( q ) ~ q −5∕3 scaling of the kinetic energy spectrum of inertial turbulence with the wavevector q . In…

Hydrodynamic instabilities, waves and turbulence in spreading epithelia.

The nonlinear regime of waves is studied, deriving an exact map of the model into the complex Ginzburg-Landau equation, which provides a complete classification of possible nonlinear scenarios and could explain the chaotic dynamics often observed in epithelia.

Anomalous Chained Turbulence in Actively Driven Flows on Spheres.

A generalized covariant Navier-Stokes model for fluid flows driven by active stresses in nonplanar geometries is introduced and the analytical tractability of the theory is demonstrated through exact stationary solutions for the case of a spherical bubble geometry.
...