Computational Analysis of Flow Dynamics and Angular Inclination Effects on Single-Axis Solar Tracking Systems for Renewable Energy Applications

Abstract

This study presents a computational fluid dynamics (CFD) investigation of the flow dynamics and angular inclination effects on a single-axis PV tracker over the full rotation range of 0-90°. A three-dimensional Reynolds-Averaged Navier-Stokes (RANS) model with the SST k-ω turbulence closure was used to resolve pressure distribution, velocity streamlines, vortex formation and turbulence intensity around the panel, and to quantify drag/lift coefficients, wind-induced torque, bending and overturning moments as functions of tilt angle and wind speed. Results indicate that the drag coefficient increased monotonically from 0.06 at 0° to 1.96 at 90°, while the lift coefficient peaks near 40-45° (Cₗ = 1.15), and flow separation with strong wake recirculation became pronounced beyond 55- 60°. Three critical inclination angles were identified approximately 25° (vortex-induced vibration risk), 45° (maximum overturning moment) and 90° (maximum drag/stow-limit), at which structural risk was elevated. Energy-yield analysis shows that wind-induced deflection and micro-shading reduce net output by up to 8-10% at high tilt angles under strong wind, and CFD predictions agreed with experimental/wind-tunnel drag data within 2-8% deviation, confirming model accuracy. Based on the combined aerodynamic and energy-yield analysis, a safe and efficient operating envelope of approximately 15-45° is recommended, together with design guidelines covering stow strategy, axis height, material selection and damping requirements for trackers deployed in high-wind regions. The findings provide a quantitative basis for improving the aerodynamic reliability and energy performance of single-axis solar tracking systems.