The effects of a novel baffle-based collector on the performance of a photovoltaic/thermal system using SWCNT/Water nanofluid

The paper presents a novel baffle-based collector for a photovoltaic/thermal system (PVT) to increase output from the system using solar power. A three-dimensional numerical model of the baffled-based PVT system was developed using the Finite volume scheme and pure water and SWCNT/Water nanofluid as the working fluids. Validation of the model was carried out using experimental and numerical results. The results of both tests showed that the relative errors of the results were less than 2.25\% and 3.54\%, respectively, which confirmed the model's accuracy. We evaluated the effects of concentration of SWCNT nanofluid, solar radiation, and flow rate on both panel cells and outlet fluid flow temperatures and also on PVT systems' electrical and thermal efficiency, using both baffle and simple channel heat collectors. The proposed baffle-based collector outperforms the straightforward collectors in all examined cases. As a result of the baffles installed in the collector, the heat transfer area and convectional heat transfer coefficient are increased, which leads to better heat transfer between the solar cells and the collector fluid. As the baffles in the collector disrupt the flow, vortices are generated, which increases the rate of heat absorbed from the PV panel by the working fluid. The solar panel temperature increases less with a baffled collector system than with a simple one as more solar radiation is captured. Additionally, in the baffle-SWCNT-based PVT framework, solar cell temperature decrease by 3.83\%, and outlet temperature, electrical and thermal efficiencies increase by 1.63\%, 0.83\%, and 4.39\%, respectively, in comparison with the simple collector. The baffle-water-based system's overall efficiency is 66.45\%, while the simple-water-based system is 63.85\%. Among the obtained results, the SWCNT/water nanofluid does not offer a significant advantage over the water-based PVT module. Furthermore, the baffle-water-based PVT system was chosen as the optimal case in this study.