A Parametric Study on the Aerodynamic Parameters of Desert Photovoltaic Arrays: The Effect of Spacing on Friction Velocity and Roughness Length

Desert photovoltaic (PV) plants suffer significant efficiency loss due to dust deposition, which is closely linked to near-surface aerodynamic conditions. This study investigates how PV array row spacing influences key aerodynamic parameters. Numerical simulations using the Realizable k-ε turbulence model were performed for multi-row arrays with varying normalized spacings (D/L = 0, 0.5, 1, 1.5, 2). Results show that the friction velocity and aerodynamic roughness length initially increase, then decrease with row number before stabilizing. Their stabilized values exhibit a positive linear correlation with D/L. Empirical formulas were fitted. These findings provide a theoretical basis for optimizing the layout of desert PV plants to mitigate dust-related efficiency losses.