Experimental investigation of heat transfer inside a channel from discrete heaters with surfaces extended by aluminum foam material

In this study, convection heat transfer inside a channel from discrete heaters with surfaces extended by aluminum foam material having pore density of 10, 20 and 40 PPI has been investigated experimentally and under laminar and turbulent flow conditions. Air was used working fluid. The lower surface of the channel were equipped with 8x2 discrete aluminum foam blocks subjected to uniform heat flux. The experimental study was made for, Reynolds numbers 531-4486 and modified Grashof numbers 4,2x107- 1,7x108. The row-averaged Nusselt number distributions and the effect of modified Grashof and Reynolds number and also pore density of the aluminum foams on the buoyancy-driven secondary flow have been investigated. In the result of the study, under laminar flow conditions, the comparisons made between foams having different pore densities show that 10 PPI foam blocks display higher thermal performance than the 20 PPI and 40 PPI because of its high permeability and low pore density characteristics. And also obtained results represent that, using the foam material show 2,5 times higher heat transfer than no foam material in the channel.KEYWORDS: Heat transfer, aluminum foam material, channel flow