Abstract
The current paper describes the characteristics of the tip vortex in the near wake of a three-bladed upwind horizontal axis wind turbine with a rotor diameter of 3 m. Phase-locked stereo particle image velocimetry measurements were carried out under the influence of the wind tunnel walls that create a high blockage ratio. The location of the vortex, convection velocity, core radius, and strength were investigated and compared with similar investigations, including different blockages cases. Additionally, the same performance of the wind turbine model was simulated in the open source wind turbine tool QBlade, using the lifting line free vortex wake module in the absence of the walls.The results showed that the location of the tip vortices was more inboard the tip and more downstream the tunnel compared to the simulations and similar experiments. The convection velocity remained similar in the axial direction and changed in the lateral direction, contributing to the delay of the movement of the tip vortex outboard the tip. The strength, based on the circulation, was found with a difference of 4% between simulation and experiment.
Highlights
Wake effects and their interaction play a significant role in wind farm layout and performance
The current paper describes the characteristics of the tip vortex in the near wake of a three-bladed upwind horizontal axis wind turbine with a rotor diameter of 3 m
This paper aims to characterize the effect of the wind tunnel walls on the tip vortices (TVs)
Summary
Wake effects and their interaction play a significant role in wind farm layout and performance. The wake of a single wind turbine is strongly affected by the shedding of the tip vortices (TVs). They are responsible for the complex flow field in the wake, producing strong gradients and instabilities [1]. For this reason, TVs have received significant attention within the wind energy research community. N.J. Vermeer carried out several studies in the wake of a rotor model using a radial traverse equipped with hotwire probes that highlighted important conclusions for further research: The TV structure does not travel with the average velocity between inside and outside the wake, as was used under the assumption of roller bearing [2]. Its diameter decreases by expanding the wake while increases its diameter by aging [5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
