Enhancing radiator cooling capacity: A comparative study of nanofluids and water/EG mixtures

The present study experimentally investigates and compares the performance of a radiator system cooled by a water-ethylene glycol (70:30) based Al₂O₃-SiO₂-TiO₂ nanofluid, with that of a radiator cooled by a water/EG mixture. The equal pumping power criterion of the pump with an equal mass flow rate was used for comparison. Mass flow rate and nanoparticle volume fraction on a radiator cooling system and the radiator's capacity have been studied. Five different nanofluids were prepared with different composition ratios of Al₂O₃-SiO₂-TiO₂ with a total of 0.45 % nanoparticles. The flowrate changed in the range of 0.02-0.032 kg/s. The results showed that the increase in heat transfer is mainly due to the flow velocity and the nanoparticles added in different proportions to the base liquid. The UA value and enhancement ratio of NF1 compared to EG/W is 14-18.5 %, for NF2 it is 14.9-21.8 %, for NF3 it is 15.1-23.4 %, for NF4 it is 15.6-27.5 %, and for NF5 it is 15.9-30 % at 0.02 kg/s and 0.032 kg/s. According to the experimental study results, nanofluids with low concentrations of nanoparticles can enhance the heat transfer rate up to 30 % as a comparison with water/EG.