Thermo Physical Properties and Heat Transfer Performance of Ethylene Glycol + Water mixture based Al2O3 Nanofluids: A Review

Nanofluids are the liquids added to the list of new generation heat transfer fluids and are being preferred over conventional heat transfer fluids in recent years. Thermal performance of nanofluids profoundly depends on their thermo physical properties. Water, EG and EG +water mixture fluids are normally used to lower the freezing point of heat transfer liquids in heat exchangers of ice plants. In the present work, thermo physical properties, pressure drop, and heat transfer performance of Al2O3 nanoparticles suspended in EG +water mixture based fluids are reviewed at different temperatures for different concentrations. A nanoparticles suspension is considered as a three phase system including the solid phase (nanoparticles), the liquid phase (fluid media) and the interfacial phase, which contributes significantly to the system properties because of their extremely high surface to volume ratio in nanofluid. The review show that the thermal conductivities of Al2O3 nanofluid increases with the increase in the Al2O3 nanoparticle concentrations in the base fluids. Also the viscosities of nanofluid found to decreases exponentially with increase in the nanofluids temperature and marginally increases with increase in the nanoparticles concentration in the base fluids. This review would be useful in the field of secondary refrigerant.