Lattice Boltzmann Study of Hydrodynamic Spinodal Decomposition

Abstract

We study both the dynamics of dissolution of an equilibrium interface and phase separation in two-dimensional fluids using lattice Boltzmann simulations. Results for a liquid-gas system and a binary fluid are compared. For symmetric quenches in the liquid-gas system, single-phase domains grow like ${t}^{\ensuremath{\alpha}}$, where $\ensuremath{\alpha}=\frac{1}{2}$ for high viscosities (corresponding to early times), crossing over to $\ensuremath{\alpha}=\frac{2}{3}$ for low viscosities (later times). For a binary fluid the crossover is between $\ensuremath{\alpha}=\frac{1}{3}$ and $\ensuremath{\alpha}=\frac{2}{3}$. This behavior is compared to that for nonsymmetric quenches.