Articles | Volume 10, issue 10
https://doi.org/10.5194/wes-10-2137-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/wes-10-2137-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
07 Oct 2025
Research article |
| 07 Oct 2025
| 07 Oct 2025
On the wake re-energization of the X-Rotor vertical-axis wind turbine via the vortex-generator strategy
Flow Physics and Technology, Faculty of Aerospace Engineering, Delft University of Technology, Delft, the Netherlands
Andrea Sciacchitano
Flow Physics and Technology, Faculty of Aerospace Engineering, Delft University of Technology, Delft, the Netherlands
Carlos Ferreira
Flow Physics and Technology, Faculty of Aerospace Engineering, Delft University of Technology, Delft, the Netherlands
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We studied the airflow around a new type of wind turbine called the X-Rotor, which could help to reduce the cost of offshore wind energy. Comparing a computer simulation model and wind tunnel experiments, we found that the model correlates well under normal conditions but becomes less accurate when the blades pitch. Our results show that future designs of this turbine category must consider complex 3D flow effects to better predict and improve wind turbine performance.
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The wake of a scaled vertical-axis wind turbine farm was measured, resulting in the first experimental database of 3D-resolved flow-field measurements. In addition to the baseline operating conditions, two modes of wake control were tested, which involve the passive adjustment of the rotor blade pitch. The results highlight the impacts of these mode adjustments on the trailing vorticity system, wake topology, and affinity towards increasing the rate of wake recovery throughout the farm.
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Floating offshore wind turbines may experience large surge motions that, when faster than the local wind speed, cause rotor–wake interaction.
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Short summary
This study is an experimental exploration of the wake of the novel X-Rotor vertical-axis wind turbine. Passive blade pitch is used to favorably modify the wake topology and subsequent energy replenishment process. The results demonstrate significant increases in available power for downstream rotors and the underlying mechanisms, highlighting the potential of vertical-axis wind turbines and passive blade pitch control for high-energy-density wind farm applications.
This study is an experimental exploration of the wake of the novel X-Rotor vertical-axis wind...
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