Articles | Volume 11, issue 4
https://doi.org/10.5194/wes-11-1147-2026
© Author(s) 2026. 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-11-1147-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
10 Apr 2026
Research article |
| 10 Apr 2026
| 10 Apr 2026
Comparison of measured and simulated fatigue loads on a multi-megawatt wind turbine
DTU Wind and Energy Systems, Technical University of Denmark Risø Campus, 4000 Roskilde, Denmark
Vestas Wind Systems A/S, Hedeager 42, 8200 Aarhus, Denmark
Jakob Mann
DTU Wind and Energy Systems, Technical University of Denmark Risø Campus, 4000 Roskilde, Denmark
Mikael Sjöholm
DTU Wind and Energy Systems, Technical University of Denmark Risø Campus, 4000 Roskilde, Denmark
Kasper Zinck
Vestas Wind Systems A/S, Hedeager 42, 8200 Aarhus, Denmark
Karunya Raj
Vestas Wind Systems A/S, Hedeager 42, 8200 Aarhus, Denmark
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This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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Wind turbines extract energy from the incoming wind flow, which needs to be recovered. In very large offshore wind farms, the energy is recovered mostly from above the wind farm in a process called entrainment. In this study, we analyzed the effect of atmospheric stability on the entrainment process in large offshore wind farms using measurements recorded by a research aircraft. This is the first time that in situ measurements are used to study the energy recovery process above wind farms.
Felix Kelberlau and Jakob Mann
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Floating lidar systems are used for measuring wind speeds offshore, and their motion influences the measurements. This study describes the motion-induced bias on mean wind speed estimates by simulating the lidar sampling pattern of a moving lidar. An analytic model is used to validate the simulations. The bias is low and depends on amplitude and frequency of motion as well as on wind shear. It has been estimated for the example of the Fugro SEAWATCH wind lidar buoy carrying a ZX 300M lidar.
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Measuring the variability of the wind is essential to operate the wind turbines safely. Lidars of different configurations have been placed on the turbines’ nacelle to measure the inflow remotely. This work found that the multiple-beam lidar is the only one out of the three employed nacelle lidars that can give detailed information about the inflow variability. The other two commercial lidars, which have two and four beams, respectively, measure only the fluctuation in the along-wind direction.
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In this study we use state-of-the-art scanning wind lidars to investigate the wind field in the near-wake region of a mature, open-grown tree. Our measurements provide for the first time a picture of the mean and the turbulent spatial fluctuations in the flow in the wake of a tree in its natural environment. Our observations support the hypothesis that even simple models can realistically simulate the turbulent fluctuations in the wake and thus predict the effect of trees in flow models.
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Short summary
This study shows that
buoyancyof the atmosphere has a large impact on the lifetime of a wind turbine. We use measurements from one of the largest wind turbines in the world to show that this feature of the atmosphere must be considered while in the design process. Our work is also motivated by the need to update the current models of the atmosphere. Indeed, as turbines increase in size, there is a concern that the deficiencies of our models might become exposed.
This study shows that
buoyancyof the atmosphere has a large impact on the lifetime of a wind...
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