English
Related papers

Related papers: Vorticity, Defects and Correlations in Active Turb…

200 papers

Recent experiments and numerical studies have drawn attention to the dynamics of active nematics. Two-dimensional active nematics flow spontaneously and exhibit spatiotemporal chaotic flows with proliferation of topological defects in the…

Soft Condensed Matter · Physics 2020-07-08 Farzan Vafa , Mark J. Bowick , M. Cristina Marchetti , Boris I. Shraiman

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 experimental work as a low Reynolds number…

Soft Condensed Matter · Physics 2022-11-30 C. Rorai , F. Toschi , I. Pagonabarraga

We numerically study two-dimensional active nematics with periodic activity patterning. For stripes of activity, we observe a transition from two-dimensional to one-dimensional active turbulence as the maximum active force and distance…

Soft Condensed Matter · Physics 2025-03-11 Cody D. Schimming , C. J. O. Reichhardt , C. Reichhardt

Specific features of two-dimensional nematodynamics give rise to shortfalls of the tensor representation of the nematic order parameter commonly used in computations, especially in theory of active matter. The alternative representation in…

Soft Condensed Matter · Physics 2022-09-21 L. M. Pismen

Active matter systems display a fascinating range of dynamical states, including stationary patterns and turbulent phases. While the former can be tackled with methods from the field of pattern formation, the spatio-temporal disorder of the…

Fluid Dynamics · Physics 2018-08-13 Martin James , Wouter J. T. Bos , Michael Wilczek

Topological defects in active liquid crystals can be confined by introducing gradients of activity. Here, we examine the dynamical behavior of two defects confined by a sharp gradient of activity that separates an active circular region and…

Soft Condensed Matter · Physics 2021-06-16 Ali Mozaffari , Rui Zhang , Noe Atzin , Juan J. de Pablo

We perform energy spectrum analysis of the active turbulence in 3D bulk active nematic using continuum numerical modelling. Specifically, we calculate the spectra of two main energy contributions---kinetic energy and nematic elastic…

Soft Condensed Matter · Physics 2020-09-15 Žiga Krajnik , Žiga Kos , Miha Ravnik

Active processes in living systems generate nonequilibrium forces that deform embedded passive macromolecules. To understand how such dynamics influence polymer conformation, we study a flexible passive chain in an active nematic fluid.…

Soft Condensed Matter · Physics 2025-09-30 Zahra K. Valei , Davide Marenduzzo , Tyler N. Shendruk

To enhance the understanding of the behavior of active nematic, it is important to understand the behavior of topological defects. In this paper, we study the configuration of topological defects of a two-dimensional active nematic around a…

Soft Condensed Matter · Physics 2026-02-16 Hiroki Matsukiyo , Jun-ichi Fukuda

We investigate the turbulent dynamics of a two-dimensional active nematic liquid crystal con- strained on a curved surface. Using a combination of hydrodynamic and particle-based simulations, we demonstrate that the fundamental structural…

Soft Condensed Matter · Physics 2019-05-01 D. J. G. Pearce , Perry W. Ellis , Alberto Fernandez-Nieves , L. Giomi

We consider two minimal models of active fluid droplets that exhibit complex dynamics including steady motion, deformation, rotation and oscillating motion. First we consider a droplet with a concentration of active contractile matter…

Soft Condensed Matter · Physics 2016-12-20 Carl A. Whitfield , Rhoda J. Hawkins

The growing interest in active nematics and the emerging evidence of the relevance of topological defects in biology asks for reliable data analysis tools to identify, classify and track such defects in simulation and microscopy data. We…

Soft Condensed Matter · Physics 2020-02-10 Dennis Wenzel , Michael Nestler , Sebastian Reuther , Maximilian Simon , Axel Voigt

We investigate the statistical properties, based on numerical simulations and analytical calculations, of a recently proposed stochastic model for the velocity field of an incompressible, homogeneous, isotropic and fully developed turbulent…

Fluid Dynamics · Physics 2016-04-28 Rodrigo M. Pereira , Christophe Garban , Laurent Chevillard

We establish how active stress globally affects the morphology of disclination lines of a three dimensional active nematic liquid crystal under chaotic flow. Thanks to a defect detection algorithm based on the local nematic orientation, we…

Soft Condensed Matter · Physics 2025-06-30 Pasquale Digregorio , Cecilia Rorai , Ignacio Pagonabarraga , Federico Toschi

A nematic liquid crystal confined to the surface of a sphere exhibits topological defects of total charge $+2$ due to the topological constraint. In equilibrium, the nematic field forms four $+1/2$ defects, located at the corners of a…

Soft Condensed Matter · Physics 2020-07-22 Yi-Heng Zhang , Markus Deserno , Zhan-Chun Tu

We consider a phenomenological continuum model for an active nematic fluid and show a universal, model independent, instability which renders the homogeneous nematic state unstable to order fluctuations. Using numerical and analytic tools…

Soft Condensed Matter · Physics 2014-10-15 Elias Putzig , Aparna Baskaran

Morphogenesis emerges from dynamic feedback among geometry, mechanics, and chemistry; however, disentangling these contributions in living systems remains challenging. Here, we focus on the interplay between geometry and mechanics by…

Suspensions of active agents with nematic interactions exhibit complex spatio-temporal dynamics such as mesoscale turbulence. Since the Reynolds number of microscopic flows is very small on the scale of individual agents, inertial effects…

Soft Condensed Matter · Physics 2022-01-05 Colin-Marius Koch , Michael Wilczek

The modeling of turbulence, whether it be numerical or analytical, is a difficult challenge. Turbulence is amenable to analysis with linear theory if it is subject to rapid distortions, i.e., motions occurring on a time scale that is short…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Bryan M. Johnson

We show that "dry" active nematics, e.g. collections of shaken elongated granular particles, exhibit large-scale spatiotemporal chaos made of interacting dense, ordered, band-like structures in a parameter region including the linear onset…

Soft Condensed Matter · Physics 2014-09-16 Sandrine Ngo , Anton Peshkov , Igor S. Aranson , Eric Bertin , Francesco Ginelli , Hugues Chaté