Phase Separation under Shear in Two-dimensional Binary Fluids

TL;DR

This paper investigates how shear influences phase separation in 2D binary fluids using lattice Boltzmann simulations, revealing a dynamic equilibrium where domains are constantly broken and re-formed.

Contribution

It introduces a modified lattice Boltzmann method with Lees-Edwards boundary conditions to study shear effects on phase ordering in binary fluids.

Findings

Shear can induce a dynamic equilibrium state in phase separation.

Domain sizes are affected by shear rate and viscosity.

A balance between spinodal decomposition and shear-induced disordering is observed.

Abstract

We use lattice Boltzmann simulations to study the effect of shear on the phase ordering of a two-dimensional binary fluid. The shear is imposed by generalising the lattice Boltzmann algorithm to include Lees-Edwards boundary conditions. We show how the interplay between the ordering effects of the spinodal decomposition and the disordering tendencies of the shear, which depends on the shear rate and the fluid viscosity, can lead to a state of dynamic equilibrium where domains are continually broken up and re-formed.