Instabilities and turbulence-like dynamics in an oppositely driven binary particle mixture

TL;DR

This study uses particle simulations to explore complex out-of-equilibrium behaviors in a binary mixture driven in opposite directions, revealing phenomena like lane formation, jamming, oscillations, and turbulence-like flows.

Contribution

It uncovers the role of friction coefficient ratios in destabilizing lane structures and introduces a new turbulence-like phase in driven binary particle systems.

Findings

Lane formation stability depends on transverse friction coefficient.

Shear-induced disturbances lead to turbulence-like flows.

Phase diagram maps out different dynamical regimes.

Abstract

Using extensive particle-based simulations, we investigate out-of-equilibrium pattern dynamics in an oppositely driven binary particle system in two dimensions. A surprisingly rich dynamical behavior including lane formation, jamming, oscillation and turbulence-like dynamics is found. The ratio of two friction coefficients is a key parameter governing the stability of lane formation. When the friction coefficient transverse to the external force direction is sufficiently small compared to the longitudinal one, the lane structure becomes unstable to shear-induced disturbances, and the system eventually exhibits a dynamical transition into a novel turbulence-like phase characterized by random convective flows. We numerically construct an out-of-equilibrium phase diagram. Statistical analysis of complex spatio-temporal dynamics of the fully nonlinear turbulence-like phase suggests its apparent reminiscence to the swarming dynamics in certain active matter systems.