Thermal evaluation of water-based alumina nanofluid in an electronic heat sink application

Abstract

An experimental study was conducted to investigate the thermal performance of a water-based Al2O3 nanofluid in an electronic heat sink application. Heat transfer tests were carried out using 20 nm alumina particles at a concentration of 5% by mass, and a coolant temperature ranging from 47 to 57 oC. The results were compared to a baseline case using deionized water as a coolant. Thermal conductivity and viscosity tests conducted on alumina nanofluids show both parameters increase with nanoparticles mass concentration. Alumina nanofluid with 5% nanoparticles mass concentration behaves as a shear thinning fluid. Tests conducted on an electronic heat sink show heat flux and coolant heat transfer coefficient increase with bulk mass flow rate. Compared to cooling by deionized water, the average increase in the heat transfer coefficient using water-based alumina nanofluid as a coolant was about 20%, while the average increase in heat flux was about 24%. An additional decrease in the heated wall cross-section temperature between 4.1 and 4.9 oC is also seen. For the same pumping power, the presence of nanoparticles in the base fluid is shown to have a significant effect on the increase in heat transfer coefficient.