Effect of aspect ratio modification of delta winglet vortex generator with common flow-up configuration: preliminary study for solar PV cooling

Excessive solar exposure can result in elevated temperatures on solar photovoltaic (PV) panels, therefore decreasing their efficiency. To address this issue, passive cooling techniques utilizing vortex generators (VGs) can be employed to maintain optimal thermal conditions for the solar panel. The current study presents a numerical analysis using computational fluid dynamics to analyze the impact of varying the aspect ratio of the delta winglet VGs on the cooling of a solar PV system as a preliminary study. The aspect ratio was modified by altering the base width of the delta winglet while maintaining fixed heights of 20 mm and 10 mm. The investigation focused on the Nusselt number, convective heat transfer coefficients, and flow visualization to evaluate the heat transfer characteristics. The proposed method has been validated against empirical correlation for the heat transfer coefficient and Nusselt number. The findings indicate that variations in aspect ratio significantly influence heat transfer performance. Notably, the highest increase in the Nusselt number was observed for an aspect ratio of 3.0, with a height of 20 mm and a width of 60 mm, yielding an enhancement of 58.57 %. Flow visualization revealed that the adjusted aspect ratio modifies the flow distribution, thereby generating vortices within the flow.