Phase separation of binary fluids with dynamic temperature

TL;DR

This study investigates how binary fluid mixtures undergo phase separation under different thermal and viscous conditions, revealing diverse morphologies and propagation behaviors through numerical simulations.

Contribution

It introduces a coupled lattice Boltzmann and finite-difference approach to simulate phase separation with dynamic temperature effects in binary fluids.

Findings

High viscosity leads to morphology variation with thermal diffusivity.

Temperature and phase separation fronts follow power-law propagation.

Low viscosity results in rounded shapes and complex patterns.

Abstract

Phase separation of binary fluids quenched by contact with cold external walls is considered. Navier-Stokes, convection-diffusion, and energy equations are solved by lattice Boltzmann method coupled with finite-difference schemes. At high viscosity, different morphologies are observed by varying the thermal diffusivity. In the range of thermal diffusivities with domains growing parallel to the walls, temperature and phase separation fronts propagate towards the inner of the system with power-law behavior. At low viscosity hydrodynamics favors rounded shapes, and complex patterns with different lengthscales appear. Off-symmetrical systems behave similarly but with more ordered configurations.