Session: 10.5 - Non-Newtonian fluid flows

Paper Number: 158761

158761 - Heat Transfer Enhancement of an Automotive Radiator Using Hybrid Nanofluid 

Abstract: 

Efficient heat transfers in radiators are vital for the life of the engine, to avoid being overheated. Conventional fluids are inefficient in engine cooling, and alternate solutions to prolong engine life must capture enhanced heat transfer, which includes the application of nanofluids, as reported in several studies. However, there is a dearth in the report of the degree of the impact of composite nanofluids in radiators as conducted in this study, to examine the performance of an automobile radiator using different basefluids, hybrid (graphite/water-EGC) and composite (Graphite-SiO₂/water-EGC) nanofluids at different concentrations.

The impact of the thermal propertiess of each nanofluid on inlet temperature,  Nusselt, and Reynolds number were experimentally examined. An increase in volumetric fraction led to increase in the thermal conductivities of both hybrid and composite nanofluids, and as the volume fraction of EGC increased in the basefluid (w/EGC), thermal conductivity decreased. In addition, as volumetric fractions increased, increased viscosities were recorded with all the radiator fluids types. Nusselt number increased with increase in inlet temperature for basefluid and hybrid nanofluid indicating that heat transfer is more of convection than conduction. For the SiO₂-composite nanofluids, the Nusselt number decreased with increase in inlet temperature indicating that more volume of SiO₂ may result in better heat transfer by conduction. The Reynolds number of the hybrid nanofluid increased with increase in inlet temperature, indicating a potential for turbulence by 29.2% compared to the base-fluid. The presence of SiO₂ in composite nanofluids dampened turbulence by 26% causing a decrease in Reynolds number when compared to the hybrid nanofluid with increased inlet temperature. Compared to the basefluid, heat transfer rate of the hybrid and the composite nanofluids improved by 86.7 and 45.7%, showing that there is better heat transfer using the nanofluids, if adopted in an automobile radiator.

Presenting Author: Luke Onyekwere Ajuka University of Ibadan

Presenting Author Biography: Dr Luke O. Ajuka is a Lecturer in the Department of Automotive Engineering, University of Ibadan, Nigeria. He holds B.Eng., M.Sc. and Ph.D. degrees in Mechanical Engineering. He is passionate about research, hence, has presented papers both at local and international fora and published papers on automotive systems and applications in reputable peer-reviewed scopus indexed journals. His research interest includes fuels and energy, automotive cooling and applications, artificial intelligence, characterizations and applied nanotechnology.