Convective Heat Transfer in a Rectangular Channel Filled With Sintered Bronze Beads and Periodically Spaced Heated Blocks

This work numerically investigated the steady state fluid flow and heat transfer behaviors associated with a sintered porous channel that contains periodically spaced heated blocks. Some typical cases are experimentally examined in this study. The relevant varied parameters were the average bead diameter $(d)$⁠, the relative block height $(h∕H)$⁠, the relative block width $(w∕H)$⁠, the relative block spacing $(s∕H)$⁠, and the Reynolds number (Re). The numerical results revealed a lack of global recirculation in regions between the blocks, where the forced convective heat transfer was low, but the heat in those regions was transferred to the metallic block by conduction through porous media, before being dissipated into the fluid that passed over the zone above the heated block. Additionally, the relevant parameters considerably affect the local Nusselt number distribution along the periphery of the block surface. The average Nusselt number for each block decreased along the direction of the flow until it reached its fully developed value. The Nusselt number increased with $h∕H$ or Re in the fully developed region. The effect of $h∕H$ on the fully developed Nusselt number became stronger as Re increased and $w∕H$ decreased. The effects of $s∕H$ and $d$ on the fully developed Nusselt number were insignificant over the ranges of parameters considered herein (⁠$d=0.7$ and $1.16mm$⁠, $h∕H=0.12-0.59$⁠, $w∕H=0.24-0.47$⁠, $s∕H=0.24-0.7$⁠, and $Re=1019-5059$⁠). Finally, this study summarized the average Nusselt number for different configurations of the heated blocks with various $d$⁠, $h∕H$⁠, $w∕H$⁠, $s∕H$⁠, and Re.