Pore-Scale Investigation on Natural Convection Melting in a Square Cavity with Gradient Porous Media

In this paper, natural convection melting in a square cavity with gradient porous media is numerically studied at pore-scale level by adopting the lattice Boltzmann method. To generate media, Monte Carlo technique based on random sampling principle used. The effects of several factors, such as Rayleigh number, porosity structure, direction, and particle diameters are investigated detail. Based numerical data, it observed that thermal performance always depends number and, specifically, set to 106, total time obtained for case negative shorter than cases positive uniform media. However, if equal 104, which heat transfer dominated conduction, noted better other cases. have understand point, various simulations also performed we found there usually exists critical value determine Moreover, our results show influence diameter liquid fraction insignificant while has great impact when equals 106.