Experimental Investigation of Overall Heat Transfer Coefficient of Al2O3/Water–Mono Ethylene Glycol Nanofluids in an Automotive Radiator

Abstract

In this research, the overall heat transfer coefficient of Al2O3/water–mono ethylene glycol (MEG) nanofluids is investigated experimentally in a car radiator under laminar flow conditions. The experimental rig developed is similar to the automotive cooling system. The stable nanofluid used is prepared by a two-step method. Ultrasonication is done for proper dispersion of 20 nm Al2O3 nanoparticle in carrier fluid water and MEG mixture with 50:50 proportions by volume. The experimental study showed that use of a nanofluid enhances the overall heat transfer coefficient as compared to the base fluid. In this study as the nanoparticle volume fraction increases from 0% to 0.8%, the overall heat transfer coefficient also increases. It was observed that as the nanofluid inlet temperature increased from 65 °C to 85 °C, the overall heat transfer coefficient decreased. It was found that using a 0.2% volume fraction Al2O3/water–MEG nanofluid can enable a 36.69 % reduction in surface area of the radiator.