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In the present study, convection heat transfer from arrays of heat sources extended by 10 PPI (Pore Per Inch) open-cell aluminum foam heat sinks inside a horizontal channel has been investigated experimentally. Air was used as the working fluid. Aluminum foams have been placed on discrete copper blocks in a rectangular channel in order to investigate the effect of aluminum foams on electronic equipments performance. The lower surface of the channel was equipped with 8x2 array of aluminum foam heat sinks subjected to uniform heat flux. Sidewalls, the lower and upper walls were insulated. The experimental study was made for Reynolds numbers 531≤ReDh≤4486 (for laminar and turbulent flow), modified Grashof numbers Gr*Dh=4,2x107 to 2,7x108 and Richardson numbers Ri=0,008 to 1,5. From the experimental measurements, distributions of Nusselt number were calculated for different Reynolds and Grashof numbers. It is found that heat transfer rate is substantially increased by employing aluminum foam heat sinks with low pore density due to relatively intense air through the aluminum foam heat sinks. As a result of comparisons, using of 10 PPI aluminum foam heat sinks increases the heat transfer rate in the channel between approximately 36% and 70% compared to the rate obtained without the foam heat sinks in a channel. [ABSTRACT FROM AUTHOR]

In this study, mixed convection heat transfer in a channel containing aluminum porous blocks having pore density of 10, 20 and 40 PPI is investigated steady, two dimensional laminar flow conditions and numerically. The problem is solved with CFD (Computational Fluid Mechanics) method in FLUENT packet program. The upper and the lower walls of the channel were thermally insulated and uniform heat flux was subjected to the bottom of the blocks. Governing equations were solved by control volume method using the suitable boundary conditions. The numerical study was made for Reynolds number 161 to 1048, Richardson number 86,45 to 2,05 and heat flux 150 to 450 W/m2. From the obtained results, it was seen that the first row of the blocks showed almost 2-4 times higher thermal performance than that of the other rows through the channel. Due to low pore density, high permeability and low flow resistance, 10 PPI porous blocks displayed approximately 38% and 63% higher thermal performances than those of 20 and 40 PPI respectively. [ABSTRACT FROM AUTHOR]