Space-Time Loadings on Wind Turbine Blades Driven by Atmospheric Boundary Layer Turbulence

the interactions between the spatio-temporal loadings on wind turbine blade blades and the turbulence structure of the neutral and moderately convective atmospheric surface layer by combining the Blade Element Method incorporated in the FAST/AeroDyn codes from NREL with a dynamic stall model with large-eddy simulation (LES) of the atmospheric boundary layer (ABL). The inow conditions were obtained from high-resolution LES interpolated to the turbine blade. The central aim of our analysis is to search for and quantify direct causal relationships between specic space-time variabilities in the turbulent inow velocity eld and the spatio-temporal variability of forces on the turbine blades, and the integrations along the blade span that produce time variations in bending moment at the hub and shaft torque. A related interest is the impact of an accurate versus inaccurate predictions of shear rate by the LES. We nd that atmospheric turbulence is a major contributor to blade loadings and that the distribution of force uctuations is sensitive to the specic structure of ABL turbulence. A well designed, accurate LES model has signicant advantages for quantifying the role of atmospheric turbulence on wind turbine performance.