Vorticity, Defects and Correlations in Active Turbulence

Abstract

We describe a numerical investigation of a continuum model of an active nematic, concentrating on the regime of active turbulence. Results are presented for the effect of three parameters, activity, elastic constant and rotational diffusion constant, on the order parameter and flow fields. Defects and distortions in the director field act as sources of vorticity, and thus vorticity is strongly correlated to the director field. In particular the characteristic length of decay of vorticity and order parameter correlations is controlled by the defect density. By contrast the decay of velocity correlations is determined by a balance between activity and dissipation. We highlight the role of microscopic flow generation mechanisms in determining the flow patterns and characteristic scales of active turbulence and contrast the behaviour of extensile and contractile active nematics.

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Cited by in corpus (69)

• Active Turbulence
• Defect dynamics in active nematics
• Turbulent dynamics of epithelial cell cultures
• Stabilization of active matter by flow-vortex lattices and defect ordering
• Defect-mediated morphologies in growing cell colonies
• Onset of meso-scale turbulence in living fluids
• Taming active turbulence with patterned soft interfaces
• Universal scaling of active nematic turbulence
• Defect unbinding in active nematics
• Cell division: a source of active stress in cellular monolayers
• Correlation lengths in hydrodynamic models of active nematics
• Active turbulence in active nematics
• Lattice Boltzmann Methods and Active Fluids
• Insensitivity of active nematic dynamics to topological constraints
• Polar jets of swimming bacteria condensed by a patterned liquid crystal
• Active nematic materials with substrate friction
• Optimal Control of Active Nematics
• Probing the shear viscosity of an active nematic
• Confinement controlled bend instability of three-dimensional active fluids
• Filopodia rotate and coil by actively generating twist in their actin shaft
• Three-Dimensional Active Defect Loops
• Design of nematic liquid crystals to control microscale dynamics
• Negative stiffness and modulated states in active nematics
• Multiscale modeling and simulation of microtubule/motor protein assemblies
• The geometry of thresholdless active flow in nematic microfluidics
• Understanding dense active nematics from microscopic models
• Twist-induced crossover from 2D to 3D turbulence in active nematics
• Activity induced nematic order in isotropic liquid crystals
• The low noise phase of a 2d active nematic
• Hydrodynamic instabilities in active cholesteric liquid crystals
• Wrinkling instability in 3D active nematics
• Introduction to topological defects: from liquid crystals to particle physics
• Quorum-sensing active particles with discontinuous motility
• Role of friction in multidefect ordering
• Topological states in chiral active matter: dynamic blue phases and active half-skyrmions
• The role of fluid flow in the dynamics of active nematic defects
• Viscoelastic and elastomeric active matter: Linear instability and nonlinear dynamics
• Mesoscopic Simulations of Active-Nematics
• Dynamics of active nematic defects on the surface of a sphere
• Spectral energy analysis of bulk three-dimensional active nematic turbulence
• Microbial Active Matter: A Topological Framework
• Inertia drives a flocking phase transition in viscous active fluids
• Self-mixing in microtubule-kinesin active fluid from nonuniform to uniform distribution of activity
• Active Matter Invasion
• A unified field theory of topological defects and non-linear local excitations
• Scaling regimes of active turbulence with external dissipation
• Helical Flow States in Active Nematics
• Flow around topological defects in active nematic films
• Dynamical Sub-classes of Dry Active Nematics
• Weakly nonlinear analysis of pattern formation in active suspensions
• A fast Chebyshev method for the Bingham closure with application to active nematic suspensions
• Diffusiophoretic propulsion of an isotropic active colloidal particle near a finite-sized disk embedded in a planar fluid-fluid interface
• Defect dynamics in active smectics induced by confining geometry and topology
• Catapulting of topological defects through elasticity bands in active nematics
• Chirality, anisotropic viscosity and elastic anisotropy in three-dimensional active nematic turbulence
• Intrinsic flow structure and multifractality in two-dimensional bacterial turbulence
• Atomic-scale tracking of topological defect motion and incommensurate charge order melting
• Uncovering novel phase transitions in dense dry polar active fluids using a lattice Boltzmann method
• Defect turbulence in a dense suspension of polar, active swimmers
• Active nematic gel with quenched disorder
• Domain Growth Kinetics in Active Binary Mixtures
• Vector Formalism for Active Nematics in Two Dimensions
• Anti-hyperuniform Critical States of Active Topological Defects
• Vortex line entanglement in active Beltrami flows
• Orientational order and topological defects in a dilute solutions of rodlike polymers at low Reynolds number
• Flow coupling between active and passive fluids across water-oil interfaces
• Dynamical arrest in active nematic turbulence
• Active micromachines: Microfluidics powered by mesoscale turbulence
• Filamentous Active Matter: Band Formation, Bending, Buckling, and Defects