Performance Enhancement of Photovoltaic/Thermal Solar Collector with Sinusoidal Flow Channels: Numerical and Experimental Study Based on the Field Synergy Principle

To improve the efficiency of conventional photovoltaic/thermal (PV/T) collectors, this study introduces a sinusoidal flow channel designed using the field synergy principle. The channel's amplitude (3 mm) and wavelength (20 mm) are optimized to enhance heat transfer and electrical output while balancing the heat transfer‐to‐pressure drop tradeoff, ensuring high performance under low‐turbulence conditions with minimal pressure losses. Through numerical simulation and experimental verification, it is demonstrated that the sinusoidal design enhances turbulence through vortex generation and boundary layer thinning, significantly reducing thermal resistance compared to plain channels. Experimentally, the optimized channel improved thermal efficiency by 1.76% and electrical efficiency by 0.34% at 3 L min −1 , while reducing the average surface temperature by 4.89 °C. The gains diminished beyond 5 L min −1 due to boundary layer stabilization, indicating that the advantages of sinusoidal channels are more pronounced when the fluid approaches or is in a transitional state (between laminar and turbulent flow). This work advances PV/T design by 1) establishing a geometry‐driven strategy to balance efficiency tradeoffs and 2) providing experimentally validated guidelines for industrial applications where even marginal efficiency gains translate to significant long‐term energy savings. The findings offer a scalable approach for high‐performance solar collectors.