Turbulence and coarsening in active and passive binary mixtures

Phys Rev Lett. 2005 Nov 25;95(22):224501. doi: 10.1103/PhysRevLett.95.224501. Epub 2005 Nov 21.

Abstract

Phase separation between two fluids in two dimensions is investigated by means of direct numerical simulations of coupled Navier-Stokes and Cahn-Hilliard equations. We study the phase ordering process in the presence of an external stirring acting on the velocity field. For both active and passive mixtures we find that, for a sufficiently strong stirring, coarsening is arrested in a stationary dynamical state characterized by a continuous rupture and formation of finite domains. Coarsening arrest is shown to be independent of the chaotic or regular nature of the flow.