Performance Assessment of an Automobile Radiator Using Al2o3/Water,EG based Nanocoolant

Abstract

The traditional coolants like water, water blended propylene glycol or ethylene glycol were used in automobile radiators and they possess poor thermo physical properties. The best method for augmentation of heat transfer rate in automobile radiator is the usage of nanofluids as coolants. Nano fluids are the colloidal solutions prepared by diffusion of nanopowder into base fluid. In this paper, the heat transfer performance of Al 2 O 3 /Water+EG (volume=70:30) based nanofluids were experimentally investigated while used in an automobile radiator. All the experiments were conducted for different volumetric concentrations of 0.1-0.3% of nanofluids and different flow rates of 5-7 lit/min and various working temperatures ranging from 60°C -90°C. Based on the results it was observed that radiators using nanofluids show better heat transfer performance when compared with the performance while using base fluid. The maximum enhancement in convective heat transfer coefficient of 41% was recorded with 0.3 vol% concentrations operating at 75°C of radiator inlet temperature and 7 lit/min flow rate when compared to base fluid.In the current investigations, the performance of an automobile radiator using Al 2 O 3 / water+EG based nanofluids is experimentally investigated. The results stated that nanofluids indicate better heat transfer performance compared to base fluids. The experimental results show that Nu increases in increasing the volumetric concentration of nanoparticles and increasing fluid flow rate. A maximum of 41% enhancement in Nu was recorded with 0.3 vol% and 75°C of radiator inlet temperature with 7 lit/min flow rate. The results also state that the nusselt number increases with the rise of radiator inlet temperature. Dynamic viscosity and Thermal conductivity of nanofluids were increased with the increase of the volumetric concentration of nanoparticles. Brownian Movement of nanoparticles is also an important factor that influences the heat carrying capacity of the nanofluid. The above results motivate the design engineers to develop compact and efficient radiators for automobiles.