209 格子ボルツマン法を用いた多孔質体内の熱流動解析(S37-1 CFDの新展開(1),S37 CFDの新展開)  [in Japanese] 209 Simulation of thermal flows in porous media using the Lattice Boltzmann scheme  [in Japanese]

The lattice Boltzmann method (LBM) is adopted to simulate natural convection in porous media at the representative elementary volume (REV) scale. The influence of porous media is considered by including the porosity into the equilibrium distribution function and by adding a force term to the evolution equation. The temperature field is simulated by a simplified thermal energy distribution function which neglects the compression work done by the pressure and the viscous heat dissipation. A comprehensive parametric study of natural convective flows is carried out for various values of Rayleigh number (Ra), of Darcy number (Da), and of porosity (ε). The results of the LBM indicate that the average Nusselt number (Nu) increases with the fluid Rayleigh number, the Darcy number, or the porosity of the medium. The comparison with those of earlier studies shows good quantitative agreement for the whole range of Darcy and Rayleigh numbers. It is reasonably concluded that the lattice Boltzmann method may have applicability to simulate natural convection in porous media.