Study on Erosion Wear of Wind Turbine Blades Dominated by Stokes Numbers

Erosion of the leading edge of blades in windy and sandy environments can cause wind turbines to lose up to 25% of their annual power generation. Traditional studies have mostly focused on the impact of single factors on erosion rates, but the effects of multiple parameters on erosion rates within the framework of the Stokes number (Stk) of dust particles have not yet been clarified. This study employs a numerical approach based on the Euler–Lagrange framework, integrating the SST k-ω turbulence model with a discrete phase model (DPM) to simulate the unsteady gas–solid two-phase flow around a NACA 0012 airfoil. The computational model was rigorously validated through grid independence tests and comparison with experimental aerodynamic data from the database, showing strong agreement under steady conditions. Systematic simulations were conducted with particle diameters ranging from 10 to 360 μm, densities from 2650 to 3580 kg/m3, and inflow velocities from 1.5 to 21 m/s, comprehensively covering Stokes number regimes from Stk << 1 to Stk >> 1. Through parametric analysis, we quantify the control effect of Stk on erosion rate and erosion hot spots. Simulation results indicate that Stk has a zone-specific control effect on airfoil erosion: erosion hot spots in low-Stk zones migrate from the mid-to-rear edge to the leading edge. Erosion rate peaks when Stk ≈ 0.8. Inertial impact in the high-Stk zone dominates surface damage propagation. Based on the simulation results, an erosion model with an error of ≤3.6% was established for the E = K∙Stka∙dpb∙vc zone, providing a quantitative physical basis to inform wind turbine blade protection strategies.