Experimental and numerical investigation of heat transfer characteristics of radiator using Graphene Amine-based nano coolant

Abstract

This work presents experimental and numerical investigations on enhancing the heat transfer performance of automobile radiators with nano-coolant flowing with different mass flow rate and at different inlet temperatures conditions. Thermal management is critical as it dictates a system's overall power output, performance, efficiency and energy utilisation. Radiators and Thermal management systems for batteries are vital in keeping automobiles operating under optimal conditions. Conventional coolants lack the ability to keep up with the increasing performance requirements of thermal management systems. Nanocoolants represent a cutting-edge advancement in heat transfer fluid, boosting conductivity without compromising essential fluid dynamics of the cooling solutions. Several investigators have worked on various nanocoolants, but less work is done on radiators. In view of this, experimental and numerical investigations were done on radiator heat transfer performance using Graphene Amine based nanocoolant with varied coolant temperatures (50 °C–80 °C) and flow rates (3 l/min to 9 l/min). Thermophysical properties of nanocoolants, such as density, thermal conductivity, viscosity, specific heat, and Prandtl number, were determined by experimental and mathematical modelling techniques and were comparable with an average deviation of 5 %. Compared to the base fluids of De-ionised water and ethylene glycol combinations, Graphene Amine based nanocoolant has exhibited advancements in heat transfer properties, showing elevated Nusselt numbers, heat transfer coefficients and heat transfer rates. The investigation into the thermal transfer properties of nanocoolants utilizing theoretical and real-world experiments shows consistency with an average deviation of 20 %. Maximum heat transfer enhancement of 154.3 % and maximum heat transfer coefficient of 3209.52 W/m2K was found for Graphene Amine at 80 °C with coolant flowing at 9 l/min, which is 83.1 % higher when compared to De-ionised Water.