  In this paper, a lattice Boltzmann model is proposed to simulate solid-liquid
phase change phenomena in multiphase systems. The model couples the thermal
properties of the solidification front with the dynamics of the liquid droplet
interface, which enables the description of the complex interfacial changes
during solid-liquid phase change process. The model treats the interfaces of
gas, liquid, and solid phases using the phase field order parameter and the
solid fraction. The volume expansion or contraction caused by the change of
properties such as density during phase change is represented by adding a mass
source term to the continuum equation. The proposed model is first validated by
the three-phase Stefan problem and the droplet solidification on a cold
surface, and the numerical results are in good agreement with the analytical
and experimental results. Then it is used to model the solidification problem
with bubbles. The results show that the model is able to accurately capture the
effect of bubbles on the solidification process, which is in good agreement
with previous work. In addition, a parametric study is carried out to examine
the dependence of the sessile droplet solidification on different physical and
numerical parameters. The results show that the droplet solidification time
increases with increasing droplet volume and contact angle.
