Active Turbulence

Abstract

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 review in sections for systems with either polar or nematic order, and with or without momentum conservation (wet/dry). Comparing to inertial turbulence, we highlight the emergence of power-law scaling with either universal or non-universal exponents. We also contrast scenarios for the transition from steady to chaotic flows, and we discuss the absence of energy cascades. We link this feature to both the existence of intrinsic length scales and the self-organized nature of energy injection in active turbulence, which are fundamental differences with inertial turbulence. We close by outlining the emerging picture, remaining challenges, and future directions.

Review for Annu. Rev. Condens. Matter Phys

References in corpus (26)

• Novel type of phase transition in a system of self-driven particles
• Spontaneous motion in hierarchically assembled active matter
• Meso-scale turbulence in living fluids
• Fluid dynamics and noise in bacterial cell-cell and cell-surface scattering
• Turning bacteria suspensions into a "superfluid"
• Hydrodynamic equations for self-propelled particles: microscopic derivation and stability analysis
• Defect dynamics in active nematics
• Active wetting of epithelial tissues
• Diffusion and spatial correlations in suspensions of swimming particles
• Data-driven quantitative modeling of bacterial active nematics
• Spontaneous flow states in active nematics: a unified picture
• Sheared active fluids: thickening, thinning and vanishing viscosity
• Excitable Patterns in Active Nematics
• Complex Spontaneous Flows and Concentration Banding in Active Polar Films
• Minimal continuum theories of structure formation in dense active fluids
• Tunable dynamics of microtubule based active isotropic gels
• Interplay of Structure, Elasticity and Dynamics in Actin-Based Nematic Materials
• Rotation and propulsion in 3d active chiral droplets
• Active nematic materials with substrate friction
• Probing the shear viscosity of an active nematic
• Spontaneous mirror-symmetry breaking induces inverse energy cascade in 3D active fluids
• Anomalous diffusion and Lévy walks distinguish active from inertial turbulence
• Multi-scale statistics of turbulence motorized by active matter
• Cascade or not cascade? Energy transfer and elastic effects in active nematics
• Motility-Induced Clustering and Meso-Scale Turbulence in Active Polar Fluids
• Intermittency measurement in two dimensional bacterial turbulence

Cited by in corpus (99)

• Self-Aligning Polar Active Matter
• A review of active matter reviews
• Swimming in Complex Fluids
• Pattern formation by turbulent cascades
• Active matter under control: Insights from response theory
• Intermittency, fluctuations and maximal chaos in an emergent universal state of active turbulence
• Activity-suppressed phase separation
• Microscopic theory for hyperuniformity in two-dimensional chiral active fluid
• Design rules for controlling active topological defects
• Glassy Dynamics in Chiral Fluids
• Spontaneous Self-Constraint in Active Nematic Flows
• Mesoscopic Simulations of Active-Nematics
• Jeffery's orbits and microswimmers in flows: A theoretical review
• Fingering Instability of Active Nematic Droplets
• Robust statistical properties of T1 transitions in confluent cell tissues
• Ising-like critical behavior of vortex lattices in an active fluid
• Emerging mesoscale flows and chaotic advection in dense active matter
• Anomalous fluctuations in homogeneous fluid phase of active Brownian particles
• Dispersion of activity at an active-passive nematic interface
• Giant vortex dynamics in confined active turbulence
• Defect Line Coarsening and Refinement in Active Nematics
• A unified field theory of topological defects and non-linear local excitations
• Coexistence of active and hydrodynamic turbulence in two dimensional active nematics
• Active nematics on flat surfaces: from droplet motility and scission to active wetting
• Transport and Energetics of Bacterial Rectification
• Nonequilibrium diffusion of active particles bound to a semi-flexible polymer network: simulations and fractional Langevin equation
• Lagrangian Manifestation of Anomalies in Active Turbulence
• Tuneable defect-curvature coupling and topological transitions in active shells
• Interplay between jamming and MIPS in persistent self-propelling particles
• Chirality, anisotropic viscosity and elastic anisotropy in three-dimensional active nematic turbulence
• Phase behaviour and dynamics of three-dimensional active dumbbell systems
• Dynamics of a Passive Droplet in Active Turbulence
• Energy transfer in simple and active binary fluid turbulence {\bf {-}} a false friend of incompressible MHD turbulence
• Vorticity phase separation and defect lattices in the isotropic phase of active liquid crystals
• Vertex model with internal dissipation enables sustained flows
• Alignment-Induced Self-Organization of Autonomously Steering Microswimmers: Turbulence, Vortices, and Jets
• Friction mediated phase transition in confined active nematics
• Crack patterns of drying dense bacterial suspensions
• Active nematic defects in compressible and incompressible flows
• Inertia drives concentration-wave turbulence in swimmer suspensions
• Coexistence of defect morphologies in three dimensional active nematics
• Defect turbulence in a dense suspension of polar, active swimmers
• Migration and deformation of a droplet enclosing an active particle
• Onset of Intermittency and Multiscaling in Active Turbulence
• Nonlinear spontaneous flow instability in active nematics
• Flow patterns and defect dynamics of active nematics under an electric field
• Active Polymer Behavior in Two Dimensions: A Comparative Analysis of Tangential and Push-Pull Models
• Pattern selection and the route to turbulence in incompressible polar active fluids
• Hydrodynamics of thermal active matter
• Self-organization and memory in an disordered solid subject to random loading
• An analytical and computational study of the incompressible Toner-Tu Equations
• Mechanochemical Topological Defects in an Active Nematic
• Boundaries control active channel flows
• Flocking turbulence of microswimmers in confined domains
• Vortex pattern stabilization in thin films resulting from shear thickening of active suspensions
• Statistical physics of active matter, cell division and cell aggregation
• Shapes and dynamic regimes of a polar active fluid droplet under confinement
• Self-organisation of auto-phoretic suspensions in confined shear flows
• Self-sustained patchy turbulence in shear-thinning active fluids
• Chaos-assisted Turbulence in Spinor Bose-Einstein Condensates
• Domain Growth Kinetics in Active Binary Mixtures
• Dynamic duos: the building blocks of dimensional mechanics
• Aligning Active Particles Py Package
• Cascades and Kolmogorov's lognormal scaling in two-dimensional bacterial turbulence
• Oscillating edge current in polar active fluid
• Micro-swimmer collective dynamics in Brinkman flows
• Active fluids form system-spanning filamentary networks
• Emergence of Local Ordering and Mesoscale Giant Number Fluctuations in Active Turbulence
• Vortex line entanglement in active Beltrami flows
• Diffusion of an Active Particle Bound to a Generalized Elastic Model: Fractional Langevin Equation
• Extended self-similarity in two-dimensional complex plasmas
• Self-organised structures in mixed active-passive suspensions due to hydrodynamic interactions
• More is less in unpercolated active solids
• Phase Separation in Mixtures of Nematic and Isotropic Fluids
• Unified description of viscous, viscoelastic, or elastic thin active films on substrates
• Rheologically tuned modes of collective transport in active viscoelastic films
• Coarsening of topological defects in 2D polar active matter
• Geometric frustration and pairing order transition in confined bacterial vortices
• Structural fluctuations in active glasses
• Mixing by squirmers in stratified fluids
• Irreversibility in scalar active turbulence: The role of topological defects
• Orientational order and topological defects in a dilute solutions of rodlike polymers at low Reynolds number
• Inertia-chirality interplay in active Brownian motion: exact dynamics and phase maps
• Active nematics in corrugated channels
• Variational bounds and nonlinear stability of an active nematic suspension
• Shape anisotropy governs organization of active rods: Swarming, turbulence, flocking, and jamming
• The importance of being discrete -- An agent-based model for active nematics and more
• Hydrodynamic stability and pattern formation in hexatic epithelial layers
• Topological defects in polar active matter
• Optimal Turbulent Transport in Microswimmer Suspensions
• Dynamical arrest in active nematic turbulence
• Nematic order condensation and topological defects in inertial active nematics
• Instabilities and turbulence in extensile swimmer suspensions
• On the temperature of an active nematic
• Fluid flow and spatiotemporal chaos in chemically active emulsions
• Work to insert a particle into an active fluid
• Control of collective activity to crystallize an oscillator gas
• Phase Separation in Active Binary Mixtures With Chemical Reaction
• Quad-cascade picture of electrokinetic turbulence