Experimental Investigations of Glycerin/Al2O3 Nanofluid in the Hydrodynamically Developing Region for Automotive Cooling Applications

Abstract

The research work presented in this paper is about the experimental investigations of the convective heat-transfer behavior of glycerin/Al2O3 nanofluids at the entry regions (hydrodynamically and thermally developing) analyzed for a boundary condition having heat flux as constant. Different concentrations of Al2O3 nanoparticles of 0.05, 0.1, and 0.15 vol.% are mixed with glycerin and water at 50:50 ratio. The mass flow rate is kept under laminar flow condition by varying the Reynolds number between 500 and 2000. The testing condition of the heater section has a diameter of 25.4 mm and a length of 500 mm is tightly wound with coil representing a heater. The thermophysical properties and the variations of Nusselt numbers are experimentally studied. The results show an enhancement of 42% of the heat-transfer coefficient at a Reynolds number–2000.