Numerical study on the permeability of frozen porous media

Porous media is an important component for energy storage, and it is of great significance to understand the heat and mass transfer mechanisms for the application of porous media in engineering. According to the Gibbs-Thomson effect, the pre-melted film may form around the walls of porous media when the temperature is below the bulk water freezing point, so the water penetration of frozen porous media is possible. However, most of the numerical works of frozen porous media were focused on the phase change that has been reported by many researchers, while few numerical works were done for the permeability. In this study, a three-phase model capable of predicting the permeability of the frozen porous media was developed, this model was based on both the MRT-LBM (multi relaxation time lattice Boltzmann mothed) and the enthalpy-based phase change method. By using this model, the permeability of the frozen porous media with different particle sizes and different frozen temperatures were well predicted due to the introduction of pre-melting temperature with the correlation coefficient R² = 0.91. Results reveal that the permeability decreases with decreasing temperature when the temperature is lower than Tm0. Furthermore, results show that the permeability decreases more slowly in porous media with smaller particle size due to the Gibbs-Thomson effect.