A lattice Boltzmann model for heat and mass transfer phenomena with phase transformations in unsaturated soil during freezing process

In this paper, a mesoscopic numerical model for simulating the heat and moisture transport phenomena in frozen soil during freezing process is presented. The model includes a stochastic generation-growth method for reconstructing the soil structure with given macroscopic geometric parameters, a lattice Boltzmann method (LBM) model for solving multiphase fluid flow and a LBM model for solving heat conduction with phase change in porous media. By using the present model, freezing process in sandy loam soil is demonstrated. Two types of boundary condition, prescribed temperature and adiabatic boundary conditions are employed in the given cases. All the numerical results show good agreement with experimental results. Considering the mesoscopic nature of LBM, the proposed model is a potential alternative to traditional continuum models.