EXPERIMENTAL STUDY ON HEAT TRANSFER ENHANCEMENT USING MGO-ZNO/WATER HYBRID NANOFLUIDS IN AN AUTOMOTIVE RADIATOR

Abstract

Advances in world technology are becoming smaller and more efficient, hence management of heat is becoming a burning issue among researchers. The usage of nanoparticles is advancing industry and research by improving the thermal characteristics of conventional heat transfer fluids. The focus of this study is on the application of water-based MgO-ZnO hybrid nanofluids for thermal management of an automotive radiator. A flat tube with a louvered fin-type radiator was used as a heat exchanger for this study. Hybrid nanofluids of different volumetric concentrations (0.02%, 0.04%, and 0.06%) were experimentally tested for understanding their heat transfer performance characteristics. The test liquids were flowed through the radiator, which consisted of 37 vertical tubes, and forced convection heat transfer was done by a fan that provided a cross-air flow inside the tube bank at a constant speed. The experiment was carried out varying flow rates in the range of 6-14 liters per minute (LPM) and a constant radiator inlet temperature at 70 °C. The results demonstrate that all concentrations of hybrid nanofluid showed enhancement in heat transfer compared to the pure base fluid. Along with the convective heat transfer coefficient, it was increased by 23.4%, 32.5%, and 42.3% compared to the base fluid at 0.02%, 0.04%, and 0.06% volume concentrations, respectively. Also, the Nusselt number was increased by 9.3%, 16.1%, and 22.5% when 0.02%, 0.04%, and 0.06% volume concentrations of MgO-ZnO/Water hybrid nanofluid were used, respectively.