A numerical study of heat transfer of a porous block with the random porosity model in a channel flow

Abstract

In this paper, heat transfer of a hot plate with a porous block in a channel flow is numerically investigated. A porous block is simulated as a fin type heat sink. The random/artificial porosity models are used to generate the distribution of porosity. In fact, the distribution of porosity in porous medium is irregular, thus the random porosity model is more realistic than the constant or variable porosity model to describe the phenomena happening in porous medium. Therefore, the distribution of porosity of porous block obeys the random porosity model, and the factors of mean porosity and standard deviation are taken into consideration. The variations of the porosity and the velocity in porous block are no longer smooth. For obtaining more heat transfer rate, the artificial porosity model is proposed. The heat transfer rates of the several cases derived by the artificial porosity model are better than those of the random porosity model. The thermal performance of porous block is larger than that of solid block as the mean porosity is larger than 0.5.