Analysis of aerodynamic loads on vertical axis wind turbines considering the Coriolis effect

This study systematically investigates the aerodynamic loads of a 300W H-type vertical axis wind turbine, focusing on the critical role of the Coriolis force in lateral loads. Through wind tunnel experiments, Computational Fluid Dynamics (CFD) simulations, and a dual-actuator disk stream tube model, the Coriolis force is, for the first time, confirmed as the physical origin of the non-zero mean lateral force based on the Navier-Stokes equations in a rotating frame. The Coriolis force, acting only in the lateral direction, is constant and theoretically proportional to the product of rotational speed and incoming wind velocity. Under high wind speed, the lateral load dominated by the Coriolis force can induce a significant cumulative effect, resulting in non-negligible overturning moments, which imposes new requirements on tower design and stability analysis. Incorporating Coriolis corrections into the multiple stream tube model reduces the lateral force prediction error to below 15 % across a 4–10.1 m/s wind speed range. The CFD simulation demonstrates superior predictive capability compared to the stream tube model due to its complete reconstruction of the inertial force system in the rotating flow field, with an average relative error of 13.4 % in lateral load predictions against experimental data. Statistical analysis of experimental data confirms that the aerodynamic loads exhibit strong non-Gaussian characteristics. Frequency analysis of experimental data reveals 3 times and 6 times rotational frequency components in thrust and lateral forces, respectively, offering key insights for resonance risk assessment.