At the pore scale level, 2-D porous medium structures of porous media with different porosities (isotropic) and the same porosities (anisotropic) were constructed using quartet structure generation set. A random porous cavity was selected and combined with the lattice Boltzmann model to describe the gas-liquid phase transition process. Bubble generation, growth, mutual fusion, and collision as well as rebound process in porous media framework were investigated by simulating the phase transition phenomenon in porous media. Calculation results show that in three different heat loads, the maximum relative errors between the qualities of gas phase and liquid phase and theoretical solution of gas phase were 0.09%, 0.19%, and 0.32%, respectively, whereas the values for liquid phase were 0.11%, 0.38%, and 1.49%, respectively. Simulation results coincide with the theoretical solution perfectly, verifying the accuracy and feasibility of the model for random porous structures.
Application of lattice Boltzmann method to phase transition process