Title: Improved thermal lattice Boltzmann model for simulation of liquid-vapor phase change,
Abstract: In this paper, an improved thermal lattice Boltzmann (LB) model is proposed
for simulating liquid-vapor phase change, which is aimed at improving an
existing thermal LB model for liquid-vapor phase change [S. Gong and P. Cheng,
Int. J. Heat Mass Transfer 55, 4923 (2012)]. First, we emphasize that the
replacement of \[{\left( {\rho {c_V}} \right)^{ - 1}}\nabla \cdot \left(
{\lambda \nabla T} \right)\] with \[\nabla \cdot \left( {\chi \nabla T}
\right)\] is an inappropriate treatment for diffuse interface modeling of
liquid-vapor phase change. Furthermore, the error terms ${\partial_{t0}}\left(
{Tv} \right) + \nabla \cdot \left( {Tvv} \right)$, which exist in the
macroscopic temperature equation recovered from the standard thermal LB
equation, are eliminated in the present model through a way that is consistent
with the philosophy of the LB method. In addition, the discrete effect of the
source term is also eliminated in the present model. Numerical simulations are
performed for droplet evaporation and bubble nucleation to validate the
capability of the improved model for simulating liquid-vapor phase change.
Numerical comparisons show that the aforementioned replacement leads to
significant numerical errors and the error terms in the recovered macroscopic
temperature equation also result in considerable errors.