Free-vortex models for wind turbine wakes under yaw misalignment

Free-vortex models for wind turbine wakes under yaw misalignment: a validation study on far-wake effects

van den Broek, M.J. (TU Delft Team Jan-Willem van Wingerden)
De Tavernier, D. (TU Delft Wind Energy)
Hulsman, Paul (University of Oldenburg)
van der Hoek, D.C. (TU Delft Team Jan-Willem van Wingerden)
Sanderse, Benjamin (Centrum Wiskunde & Informatica (CWI))
van Wingerden, J.W. (TU Delft Team Jan-Willem van Wingerden)

2023

Near-wake effects of wind turbine models using the free-vortex wake have been studied extensively, but there is a lack of validation for such predictions in the mid to far wake. This paper presents a novel validation study using three free-vortex wake models of increasing complexity: an actuator disc, an actuator disc with rotation, and a lifting-line model. We emphasise the application for dynamic wind farm flow control optimisation with a focus on wake redirection using yaw misalignment. For this purpose, wake models should provide sufficiently accurate power predictions at a low computational expense to enable real-time control optimisation. Three sets of wind tunnel data are used for validation: flow measurements under steady yaw misalignment, time-resolved flow measurements for a step change in yaw, and turbine output measurements with yaw control and simulated wind direction variation. Results indicate that the actuator-disc model provides the best balance between computational cost and accuracy in power predictions for the mid to far wake, which is not significantly improved upon by the addition of rotation. In the near wake, the added complexity of the lifting-line model may provide value as it models blade loading and individual tip vortices. Altogether, this study provides important validation for further studies into optimisation of wake steering under time-varying conditions and suggests that the actuator-disc model is a suitable candidate for use in a model-predictive wind farm flow control framework.

http://resolver.tudelft.nl/uuid:44e2881b-ac13-4d34-89ab-8defad29ae9f

https://doi.org/10.5194/wes-8-1909-2023

2366-7443

Wind Energy Science, 8 (12), 1909-1925

Institutional Repository

journal article

© 2023 M.J. van den Broek, D. De Tavernier, Paul Hulsman, D.C. van der Hoek, Benjamin Sanderse, J.W. van Wingerden