Exploring the performance of horizontal axis wind turbine in yawed turbulent flows through wind tunnel experiments

Horizontal Axis Wind Turbines (HAWTs) inevitably operate in yawing and turbulent flows and thus demand a clear understanding of their performance in these flow environments. This study presents experimental investigations of a scaled HAWT model tested in an atmospheric boundary layer wind tunnel, focusing on the effects of turbulence intensity and yaw angle on performance. Comprehensive tests and analyses were carried out to elucidate the structural responses and dynamic/aerodynamics characteristics of the HAWT. Through scale conversion relationships, we bridge the gap between model and prototype, while numerical fitting that is based on the experimental results unveils overarching trends of the HAWT behavior. The results indicate that the performance of HAWTs is significantly related to turbulence intensity and yaw angle. The nacelle displacement of HAWTs may exceed operational limits with high turbulence and extensive yaw. Moreover, a notable interplay between tip speed ratio and natural frequency can be observed, alongside a significant impact of yaw angle on power coefficient. This experimental study not only enhances our comprehension of HAWT dynamics but also furnishes invaluable insights into their operational intricacies across diverse inflow scenarios.