Magnetic nanofluid-enhanced dimpled minichannels: A cutting-edge approach for solar photovoltaic cooling

This computational study aims to explore the heat transfer characteristics and fluid flow behavior of Fe3O4, which can be used as a cooling fluid for solar photovoltaic (PV) panels, through reentrant circular cavitied mini-channels. The flow of magnetic Fe3O4 through mini-channels is dealt with at various pitch lengths of 4, 5, and 6 mm. Active heat transfers are ensured by varying the magnetic field intensity from 800 G to 2000 G of single source magnets, which are at different positions from the inlet. Various Reynolds numbers ranging from 50 to 210 were investigated. The method allowed for an induction of vortices, leading to an enhancement of heat transfer. As a result, enhanced trends of the Nusselt number, friction factor, Colbourn j-factor, and thermal enhancement factor (TEF) were determined by changing the parameters. An enhancement of the Nusselt number has been observed, due to an increase in magnetic field strength, pitch, and position of single-sourced magnets, with an increase of up to 64.2%. Friction factor and Colbourn j-factor both have a decreasing trend in all cases for increasing values of Re. A notable reduction in the friction factor of up to 11.15% has been observed. The TEF has been noted to be greater than one in all cases, reaching the maximum of 1.568, through which the best-suited geometry and flow parameters have been recommended. This study highlights the potential of the proposed approach for efficient cooling of PV panels, effectively addressing heating challenges.