| 04 Dec 2025
Dynamics of floating wind turbine wakes in a wind tunnel setup
Abstract. The wake of a laboratory-scale wind turbine model is investigated in high-detail in a wind tunnel setup under prescribed surge, sway, roll, pitch, yaw and coupled surge-pitch motions using large-eddy simulations coupled to an actuator-line model. The goal is to assess how the wake of a moving turbine evolves in a high blockage ratio scenario and how it compares with the results found in the literature for full-scale models and experiments. This manuscript also extends the state-of-the-art to more degrees-of-freedom. Two cases per degree-of-freedom are considered: one with a low Strouhal number St and high normalized amplitude A*, and vice versa. Cases with low-St/high-A* exhibit a wake behavior similar to the fixed-bottom case. Conversely, cases with a high-St/low-A* disturb the wake to a much larger extent. The contrast is caused by differences in how much the wake amplifies the perturbations of the floating motion upstream and is particularly noticeable at the blade tip and root trails. Prescribed motions with a component perpendicular to the flow are found to have a larger impact than motions exclusively in the flow direction. Overall, the phenomena found in the literature are well captured in this setup.
Competing interests: The authors have the following competing interests: RA, DvT and AV declare that they have no conflict of interest. FHM, KL and PD declare that they were full-time employees of Siemens Gamesa Renewable Energy at the time this work was carried out.
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Dear Authors,
I was invited by the Associate Editor to review your manuscript and was pleased to accept, as the topic is of strong interest to me and closely aligned with my recent research activities. In recent years, the wind energy community has shown increasing interest in the aerodynamics and wake interactions of floating wind farms, making the subject of this manuscript timely and potentially relevant to the readership of Wind Energy Science.
The results presented contribute to the growing body of research produced by several research groups in this area. While the findings are interesting, it would be beneficial to more clearly position them within the existing literature. In particular, the manuscript should better clarify whether the results are novel, whether they represent a complementary investigation of previously studied phenomena, and to what extent they agree or differ from existing studies. This contextualization is not always sufficiently clear in the current version.
Overall, I believe the manuscript is suitable to proceed in the review process at Wind Energy Science and may be considered for publication, provided that the authors adequately address the reviewers’ comments.
General comments
Specific comments
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References
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