“Heat transfer analysis in 10 PPI copper metal foam using graphene-water nanofluid: Experimental study”

Abstract

Thermal management of the modern electronic devices is one of the critical areas where innovative approaches are explored that include cooling using liquid, phase change materials, and employing microchannels, and porous metal foams along with the use of nanofluid. There are numerous analytical and simulation studies along with few experimental studies that used different water-nanoparticles (viz., CuO, Al₂O and TiO₂) combinations to flow through the metal foam to enhance the heat transfer. However, the use of Graphene-H₂O nanofluid along with porous metal foam is not much explored. This study investigates the thermal performance and hydraulic features of Graphene-H₂O nanofluid since it has some unique thermal characteristics which differentiate it from other nanofluids. Further, slightly wider range of Reynolds number is addressed which extends from 300 to 1900, as against up to 1200 in the earlier studies. The volumetric concentrations (φ) of Graphene are varied from 0.1 % to 0.5 %. The investigation is carried out for a cavity that contains copper metal lattice porous structure having 95 % porosity and 10 PPI pore density. The parameters addressed include heat transfer coefficient, Nusselt number, average wall temperature of metal foam, pressure drop & friction coefficient. The results revealed that the heat transfer coefficient increases with concentration of nanofluid and for 0.5 % concentration, it increases 3.81 times and 6.89 times, respectively, for Re = 315 and Re = 1895, when compared with that for plain distilled water. The corresponding significant reduction in the heat sink temperature to the tune of 10.67 % and 13.10 % is observed, respectively, for Re = 315 & Re = 1785.