Advanced Cooling of Photovoltaic Panels Using Al2O3 Nanofluid: A Numerical Study on the Influence of Flow Rate

This paper presents a parametric numerical study on the cooling performance of photovoltaic panels using water and an Al2O3-based nanofluid. The increase in operating temperature leads to a decrease in electrical efficiency, making thermal management a key factor in optimizing these systems. The analysis was carried out through numerical simulations in ANSYS, aiming to evaluate the influence of volumetric flow rate and inlet temperature of the cooling fluid on the panel cooling time under transient conditions. The results show that the performance of the Al2O3 nanofluid depends on the flow rate of the cooling fluid. At a low flow rate of 0.05 m3/h and a concentration of 4%, the cooling time is reduced by approximately 18–22% compared to water, while this advantage diminishes as the flow rate increases. A favorable operating region was also observed within the investigated laminar and near-transitional range, beyond which increasing the flow rate produced only limited additional reductions in cooling time under the assumptions of the numerical model. The findings highlight the importance of correlating the thermophysical properties of the fluid with flow parameters in order to optimize the thermal management of photovoltaic panels.