PERTANIKA JOURNAL OF SCIENCE AND TECHNOLOGY

Rapid developments in the design of chips and electronic devices for high-performance computers have necessitated new and more effective methods of chip cooling. The purpose of this study was to investigate the heat transfer characteristics of aluminium foam heat sink for the Intel core i7 processor. Three aluminium foam heat sink models were used in the study: without channels (A), with two channels (B), and with three channels (C). The aluminium foam heat sink was subjected to a steady flow of water covering the non-Darcy flow regime (541 to 1353 Reynolds numbers). The bottom side of the heat sink was heated with a heat flux between 8.5 and 13.8 W/cm2. The distributions of the local surface temperature and the local Nusselt number were measured and compared with numerical data obtained using the finite element method for all three models. The average Nusselt number was obtained for the specified range of Reynolds numbers, and an empirical correlation of the average Nusselt number as a function of the Reynolds number was derived for each model. The results revealed that the local surface temperature increases as the heat flux increases, decreasing the Reynolds number and increasing the flow direction axis for all three models. Model (A) achieved a lower local temperature than models (B) and (C). Compared with model (A), models (B) and (C) reduced the average Nusselt number by 10% and 25%, respectively. The pressure drop across the foam was also measured. The thermal efficiency index was defined in this study in order to obtain the optimal design condition for the aluminium foam heat sink models. The results revealed that the optimum design condition is model (B) at Re=1353. The numerical results were in good agreement with the local Nusselt number and the local experimental temperature with a maximum relative error of 3% and 2% respectively.