Lattice Boltzmann Study of Hydrodynamic Spinodal Decomposition

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^α, where α=1/2 for high viscosities (corresponding to early times), crossing over to α=2/3 for low viscosities (later times). For a binary fluid the crossover is between α=1/3 and α=2/3. This behavior is compared to that for nonsymmetric quenches.