Impact of magnetic fields on magnetic nanofluid heat transfer in enhanced mini-channels for high-performance cooling

Abstract

This study computationally compares various minichannel configurations to improve heat transfer efficiency and lower battery surface temperatures, ensuring safe operation and extended lifespan. Utilizing CuO/water, Fe3O4/ water and CuO + Fe3O4/ water as the coolant, the study incorporates passive methods to foil the boundary layer for eddy formation, alongside magnets to enhance eddy formation. The computational analysis evaluates heat transfer effectiveness using parameters such as the Nusselt number, friction factor, Colburn j-factor, and TEF. The velocity and the temperature profile has also been depicted to further strengthen the understanding of the fluid flow variations under the influence of magnets. The results show a 65.49 % increase in the Nusselt number compared to a plain channel with water, while the Colburn j-factor rises by 65.49 % for the CuO/ water nanofluid. Although the friction factor also sees a notable increase, the performance improving factor reaches a peak of 2 for Fe3O4/ water nanofluid. All these findings are taken at the Reynolds number of 250 when a couple of magnets are positioned at the distance of 0. 15 × 102 mm and 0. 25 × 102 mm from the entrance of the channel and the results obtained highlight the dominance of the staggered upstream ribbed configuration over other designs, making it a promising approach for cooling systems in EVs and HEVs.