Thermal lattice Boltzmann study of three-dimensional bubble growth in quiescent liquid

The complete growth process of a single bubble in quiescent liquid is simulated using a three-dimensional hybrid thermal lattice Boltzmann model. The non-equilibrium extrapolation pressure boundary condition is extended to handle the thermal multiphase flow. Unfavorable spurious currents are usually generated in the vicinity of curved interfaces when two-phase lattice Boltzmann methods are applied. Here a level-set scheme is incorporated into the simulations to accurately represent interfacial dynamics. The phase change is controlled by an equation of state automatically instead of any artificial phase change model. Hence the present simulation is more accurate and thermodynamically consistent. The temperature, velocity fields during the bubble growth are consistent with relevant theories. The bubble growth rate obtained from the lattice Boltzmann simulations agree well with the analytical solutions. The result shows that the present scheme is able to simulate the relevant thermal bubble dynamics quantitatively.