A thermal lattice Boltzmann method (LBM) for two-phase fluid flows in
nucleate pool boiling process is proposed. In the present method, a new function
for heat transfer is introduced to the isothermal LBM for two-phase immiscible fluids
with large density differences. The calculated temperature is substituted into the pressure
tensor, which is used for the calculation of an order parameter representing two
phases so that bubbles can be formed by nucleate boiling. By using this method, twodimensional
simulations of nucleate pool boiling by a heat source on a solid wall are
carried out with the boundary condition for a constant heat flux. The flow characteristics
and temperature distribution in the nucleate pool boiling process are obtained.
It is seen that a bubble nucleation is formed at first and then the bubble grows and
leaves the wall, finally going up with deformation by the buoyant effect. In addition,
the effects of the gravity and the surface wettability on the bubble diameter at departure
are numerically investigated. The calculated results are in qualitative agreement
with other theoretical predictions with available experimental data.
