High-fidelity IDDES simulation evaluating impacts of extreme wind conditions on wind turbine aerodynamic response and wake evolution

With the global wind power capacity growing steadily, wind farm construction has extended from traditional plains to diverse terrains, including mountains, hills, and offshore regions. Wind turbines face increasingly complex operating environments, where frequent extreme wind conditions threaten performance and safety. This study establishes a unified analytical framework integrating conventional wind shear, extreme vertical shear (EVS), extreme horizontal shear (EHS), and extreme operating gust (EOG). High-fidelity numerical simulations are conducted using the improved delayed detached eddy simulation (IDDES) model to systematically analyze the impact mechanisms of these wind conditions on aerodynamic performance and load characteristics of wind turbines. Furthermore, wake evolution characteristics are explored, and the influence mechanisms of wakes are objectively reflected through responses of the downstream turbine. Results indicate that EHS and EVS exert the most significant effects, while EOG has a relatively milder impact. Wakes amplify the effects of extreme wind conditions, causing downstream turbines to experience stronger disturbances than upstream ones, resulting in intensified multi-directional rotor moment fluctuations, pronounced power distribution non-uniformity, increased aeroelastic flutter potential, and elevated structural fatigue loads. The high shear characteristics of EHS and EVS cause significant wake deflection and induce vortex formation, which interact with the wake to generate secondary vortices, further increasing wake complexity. Although EOG has a milder effect, it still induces localized disturbances. This study provides a theoretical foundation for optimizing wind farm layouts and advancing wake control technologies, supporting the development of safer and more cost-effective wind energy technologies.