CFD analysis of different leading edge tubercles on the aerodynamic performance of NREL phase VI wind turbine blades

This study investigates the aerodynamic effects of bio-inspired leading edge modifications on the NREL Phase VI horizontal-axis wind turbine using Reynolds-Averaged Navier–Stokes (RANS) simulations. Three leading edge geometries—sinusoidal wavy, segmented arc, and spherical tubercles—were evaluated under both full-span and partial-span configurations. A parametric analysis of the sinusoidal design was conducted using both constant and variable amplitudes within a dimensionless amplitude range (Ā = 0.015–0.045), with a fixed wavelength ratio (λ/c = 0.15). The variable amplitude configuration with Ā = 0.03 demonstrated the best performance, increasing torque by approximately 7 % at the rated wind speed (10 m/s) while maintaining stable output across the entire operating range. Both the segmented arc and variable sinusoidal designs consistently improved torque across all wind speeds. In contrast, the spherical tubercle design enhanced performance only at high wind speeds (V∞ >15 m/s), with reduced efficiency at lower speeds. Implementation strategy significantly influenced performance, partial-span modifications preserved tip-flow stability and improved low-to-moderate-speed efficiency. In contrast, full-span designs improved high-speed performance by expanding low-pressure regions and suppressing flow separation, albeit with a reduction in efficiency at rated wind speeds. These findings offer practical guidance for aerodynamic optimization of wind turbine blades via biomimetic design.