Numerical and Experimental Investigation of Heat Transfer Enhancement in an Off-Road Radiator using Al ₂ O ₃ Nano Fluids

Water and ethylene glycol are considered as conventional coolants from years in automotive industry for engine cooling. With the advancements in nanotechnology, Nano fluids have become prominent in increasing the rate of heat transfer compared to that of conventional fluids. Present study enlightens the CFD simulation of Nano-fluids in a radiator with base fluid as Ethylene glycol- water and Al₂O₃ as nanoparticles at different volume concentrations. The Nano fluid rheology is simulated in Ansys-Fluent CFD tool using standard k-ε two equation turbulence model with enhanced wall treatment and a standard y plus values. Various available fluent single phase and multiphase models are evaluated and compared with the experimental results in a simple circular pipe to setup the standard simulation methodology for radiator analysis. The effective temperature dependent thermos-physical properties of Nano fluids were estimated from the literatures. The result shows that alumina oxide nano fluids enhance heat transfer compared to their own base fluid with the increase in flow rates. Pumping power is predicted at different flow rates for different concentration of nano fluids and compared with base fluid. The results are then compared with experimental results for correlation and method improvement. The paper also presents the challenges and advantages of using nano fluids for automotive applications.