Articles | Volume 9, issue 3
https://doi.org/10.5194/wes-9-665-2024
© Author(s) 2024. 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-9-665-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
20 Mar 2024
Research article |
| 20 Mar 2024
| 20 Mar 2024
Wind turbine rotors in surge motion: new insights into unsteady aerodynamics of floating offshore wind turbines (FOWTs) from experiments and simulations
Christian W. Schulz
CORRESPONDING AUTHOR
Institute for Fluid Dynamics and Ship Theory, Hamburg University of Technology, Am Schwarzenberg-Campus 4, 21073 Hamburg, Germany
Stefan Netzband
Institute for Fluid Dynamics and Ship Theory, Hamburg University of Technology, Am Schwarzenberg-Campus 4, 21073 Hamburg, Germany
Umut Özinan
Stuttgart Wind Energy, University of Stuttgart, Allmandring 5b, 70569 Stuttgart, Germany
Po Wen Cheng
Stuttgart Wind Energy, University of Stuttgart, Allmandring 5b, 70569 Stuttgart, Germany
Moustafa Abdel-Maksoud
Institute for Fluid Dynamics and Ship Theory, Hamburg University of Technology, Am Schwarzenberg-Campus 4, 21073 Hamburg, Germany
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Christian W. Schulz, Stefan Netzband, Philip D. Knipper, and Moustafa Abdel-Maksoud
Wind Energ. Sci., 9, 1941–1965, https://doi.org/10.5194/wes-9-1941-2024, https://doi.org/10.5194/wes-9-1941-2024, 2024
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The ability to perform reliable simulations of the motion behaviour of floating offshore wind turbines (FOWTs) is a key requirement for developing resource- and cost-effective designs. To support the development of suitable simulation methods, multiple improvements to the validation process of such methods are presented. These improvements allow, for the first time, the transient aerodynamic loads acting on a FOWT in a wave tank experiment to be directly compared with simulations.
Stefano Cioni, Francesco Papi, Leonardo Pagamonci, Alessandro Bianchini, Néstor Ramos-García, Georg Pirrung, Rémi Corniglion, Anaïs Lovera, Josean Galván, Ronan Boisard, Alessandro Fontanella, Paolo Schito, Alberto Zasso, Marco Belloli, Andrea Sanvito, Giacomo Persico, Lijun Zhang, Ye Li, Yarong Zhou, Simone Mancini, Koen Boorsma, Ricardo Amaral, Axelle Viré, Christian W. Schulz, Stefan Netzband, Rodrigo Soto-Valle, David Marten, Raquel Martín-San-Román, Pau Trubat, Climent Molins, Roger Bergua, Emmanuel Branlard, Jason Jonkman, and Amy Robertson
Wind Energ. Sci., 8, 1659–1691, https://doi.org/10.5194/wes-8-1659-2023, https://doi.org/10.5194/wes-8-1659-2023, 2023
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Simulations of different fidelities made by the participants of the OC6 project Phase III are compared to wind tunnel wake measurements on a floating wind turbine. Results in the near wake confirm that simulations and experiments tend to diverge from the expected linearized quasi-steady behavior when the reduced frequency exceeds 0.5. In the far wake, the impact of platform motion is overestimated by simulations and even seems to be oriented to the generation of a wake less prone to dissipation.
Roger Bergua, Amy Robertson, Jason Jonkman, Emmanuel Branlard, Alessandro Fontanella, Marco Belloli, Paolo Schito, Alberto Zasso, Giacomo Persico, Andrea Sanvito, Ervin Amet, Cédric Brun, Guillén Campaña-Alonso, Raquel Martín-San-Román, Ruolin Cai, Jifeng Cai, Quan Qian, Wen Maoshi, Alec Beardsell, Georg Pirrung, Néstor Ramos-García, Wei Shi, Jie Fu, Rémi Corniglion, Anaïs Lovera, Josean Galván, Tor Anders Nygaard, Carlos Renan dos Santos, Philippe Gilbert, Pierre-Antoine Joulin, Frédéric Blondel, Eelco Frickel, Peng Chen, Zhiqiang Hu, Ronan Boisard, Kutay Yilmazlar, Alessandro Croce, Violette Harnois, Lijun Zhang, Ye Li, Ander Aristondo, Iñigo Mendikoa Alonso, Simone Mancini, Koen Boorsma, Feike Savenije, David Marten, Rodrigo Soto-Valle, Christian W. Schulz, Stefan Netzband, Alessandro Bianchini, Francesco Papi, Stefano Cioni, Pau Trubat, Daniel Alarcon, Climent Molins, Marion Cormier, Konstantin Brüker, Thorsten Lutz, Qing Xiao, Zhongsheng Deng, Florence Haudin, and Akhilesh Goveas
Wind Energ. Sci., 8, 465–485, https://doi.org/10.5194/wes-8-465-2023, https://doi.org/10.5194/wes-8-465-2023, 2023
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This work examines if the motion experienced by an offshore floating wind turbine can significantly affect the rotor performance. It was observed that the system motion results in variations in the load, but these variations are not critical, and the current simulation tools capture the physics properly. Interestingly, variations in the rotor speed or the blade pitch angle can have a larger impact than the system motion itself.
Moritz Gräfe, Vasilis Pettas, Nikolay Dimitrov, and Po Wen Cheng
Wind Energ. Sci., 9, 2175–2193, https://doi.org/10.5194/wes-9-2175-2024, https://doi.org/10.5194/wes-9-2175-2024, 2024
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This study explores a methodology using floater motion and nacelle-based lidar wind speed measurements to estimate the tension and damage equivalent loads (DELs) on floating offshore wind turbines' mooring lines. Results indicate that fairlead tension time series and DELs can be accurately estimated from floater motion time series. Using lidar measurements as model inputs for DEL predictions leads to similar accuracies as using displacement measurements of the floater.
Christian W. Schulz, Stefan Netzband, Philip D. Knipper, and Moustafa Abdel-Maksoud
Wind Energ. Sci., 9, 1941–1965, https://doi.org/10.5194/wes-9-1941-2024, https://doi.org/10.5194/wes-9-1941-2024, 2024
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The ability to perform reliable simulations of the motion behaviour of floating offshore wind turbines (FOWTs) is a key requirement for developing resource- and cost-effective designs. To support the development of suitable simulation methods, multiple improvements to the validation process of such methods are presented. These improvements allow, for the first time, the transient aerodynamic loads acting on a FOWT in a wave tank experiment to be directly compared with simulations.
Mohammad Youssef Mahfouz, Ericka Lozon, Matthew Hall, and Po Wen Cheng
Wind Energ. Sci., 9, 1595–1615, https://doi.org/10.5194/wes-9-1595-2024, https://doi.org/10.5194/wes-9-1595-2024, 2024
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As climate change increasingly impacts our daily lives, a transition towards cleaner energy is needed. With all the growth in floating offshore wind and the planned floating wind farms (FWFs) in the next few years, we urgently need new techniques and methodologies to accommodate the differences between the fixed bottom and FWFs. This paper presents a novel methodology to decrease aerodynamic losses inside an FWF by passively relocating the downwind floating wind turbines out of the wakes.
Fiona Dominique Lüdecke, Martin Schmid, and Po Wen Cheng
Wind Energ. Sci., 9, 1527–1545, https://doi.org/10.5194/wes-9-1527-2024, https://doi.org/10.5194/wes-9-1527-2024, 2024
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Large direct-drive wind turbines, with a multi-megawatt power rating, face design challenges. Moving towards a more system-oriented design approach could potentially reduce mass and costs. Exploiting the full design space, though, may invoke interaction mechanisms, which have been neglected in the past. Based on coupled simulations, this work derives a better understanding of the electro-mechanical interaction mechanisms and identifies potential for design relevance.
Qi Pan, Dexing Liu, Feng Guo, and Po Wen Cheng
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2024-44, https://doi.org/10.5194/wes-2024-44, 2024
Revised manuscript under review for WES
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The floating wind market is striving to scale up from a handful of prototypes to gigawatt-scale capacity, despite facing barriers of high costs in the deep-sea deployment. Shared mooring is promising in reducing material costs. This paper introduces a comprehensive design methodology for reliable shared mooring line configurations, and reveals their potential for cost-saving and power enhancement. These findings contribute to achieving cost-effective solutions for floating wind farms.
Roger Bergua, Will Wiley, Amy Robertson, Jason Jonkman, Cédric Brun, Jean-Philippe Pineau, Quan Qian, Wen Maoshi, Alec Beardsell, Joshua Cutler, Fabio Pierella, Christian Anker Hansen, Wei Shi, Jie Fu, Lehan Hu, Prokopios Vlachogiannis, Christophe Peyrard, Christopher Simon Wright, Dallán Friel, Øyvind Waage Hanssen-Bauer, Carlos Renan dos Santos, Eelco Frickel, Hafizul Islam, Arjen Koop, Zhiqiang Hu, Jihuai Yang, Tristan Quideau, Violette Harnois, Kelsey Shaler, Stefan Netzband, Daniel Alarcón, Pau Trubat, Aengus Connolly, Seán B. Leen, and Oisín Conway
Wind Energ. Sci., 9, 1025–1051, https://doi.org/10.5194/wes-9-1025-2024, https://doi.org/10.5194/wes-9-1025-2024, 2024
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This paper provides a comparison for a floating offshore wind turbine between the motion and loading estimated by numerical models and measurements. The floating support structure is a novel design that includes a counterweight to provide floating stability to the system. The comparison between numerical models and the measurements includes system motion, tower loads, mooring line loads, and loading within the floating support structure.
Wei Yu, Sheng Tao Zhou, Frank Lemmer, and Po Wen Cheng
Wind Energ. Sci., 9, 1053–1068, https://doi.org/10.5194/wes-9-1053-2024, https://doi.org/10.5194/wes-9-1053-2024, 2024
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Integrating a tuned liquid multi-column damping (TLMCD) into a floating offshore wind turbine (FOWT) is challenging. The synergy between the TLMCD, the turbine controller, and substructure dynamics affects the FOWT's performance and cost. A control co-design optimization framework is developed to optimize the substructure, the TLMCD, and the blade pitch controller simultaneously. The results show that the optimization can significantly enhance FOWT system performance.
Stefano Cioni, Francesco Papi, Leonardo Pagamonci, Alessandro Bianchini, Néstor Ramos-García, Georg Pirrung, Rémi Corniglion, Anaïs Lovera, Josean Galván, Ronan Boisard, Alessandro Fontanella, Paolo Schito, Alberto Zasso, Marco Belloli, Andrea Sanvito, Giacomo Persico, Lijun Zhang, Ye Li, Yarong Zhou, Simone Mancini, Koen Boorsma, Ricardo Amaral, Axelle Viré, Christian W. Schulz, Stefan Netzband, Rodrigo Soto-Valle, David Marten, Raquel Martín-San-Román, Pau Trubat, Climent Molins, Roger Bergua, Emmanuel Branlard, Jason Jonkman, and Amy Robertson
Wind Energ. Sci., 8, 1659–1691, https://doi.org/10.5194/wes-8-1659-2023, https://doi.org/10.5194/wes-8-1659-2023, 2023
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Simulations of different fidelities made by the participants of the OC6 project Phase III are compared to wind tunnel wake measurements on a floating wind turbine. Results in the near wake confirm that simulations and experiments tend to diverge from the expected linearized quasi-steady behavior when the reduced frequency exceeds 0.5. In the far wake, the impact of platform motion is overestimated by simulations and even seems to be oriented to the generation of a wake less prone to dissipation.
Moritz Gräfe, Vasilis Pettas, Julia Gottschall, and Po Wen Cheng
Wind Energ. Sci., 8, 925–946, https://doi.org/10.5194/wes-8-925-2023, https://doi.org/10.5194/wes-8-925-2023, 2023
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Inflow wind field measurements from nacelle-based lidar systems offer great potential for different applications including turbine control, load validation and power performance measurements. On floating wind turbines nacelle-based lidar measurements are affected by the dynamic behavior of the floating foundations. Therefore, the effects on lidar wind speed measurements induced by floater dynamics must be well understood. A new model for quantification of these effects is introduced in our work.
Roger Bergua, Amy Robertson, Jason Jonkman, Emmanuel Branlard, Alessandro Fontanella, Marco Belloli, Paolo Schito, Alberto Zasso, Giacomo Persico, Andrea Sanvito, Ervin Amet, Cédric Brun, Guillén Campaña-Alonso, Raquel Martín-San-Román, Ruolin Cai, Jifeng Cai, Quan Qian, Wen Maoshi, Alec Beardsell, Georg Pirrung, Néstor Ramos-García, Wei Shi, Jie Fu, Rémi Corniglion, Anaïs Lovera, Josean Galván, Tor Anders Nygaard, Carlos Renan dos Santos, Philippe Gilbert, Pierre-Antoine Joulin, Frédéric Blondel, Eelco Frickel, Peng Chen, Zhiqiang Hu, Ronan Boisard, Kutay Yilmazlar, Alessandro Croce, Violette Harnois, Lijun Zhang, Ye Li, Ander Aristondo, Iñigo Mendikoa Alonso, Simone Mancini, Koen Boorsma, Feike Savenije, David Marten, Rodrigo Soto-Valle, Christian W. Schulz, Stefan Netzband, Alessandro Bianchini, Francesco Papi, Stefano Cioni, Pau Trubat, Daniel Alarcon, Climent Molins, Marion Cormier, Konstantin Brüker, Thorsten Lutz, Qing Xiao, Zhongsheng Deng, Florence Haudin, and Akhilesh Goveas
Wind Energ. Sci., 8, 465–485, https://doi.org/10.5194/wes-8-465-2023, https://doi.org/10.5194/wes-8-465-2023, 2023
Short summary
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This work examines if the motion experienced by an offshore floating wind turbine can significantly affect the rotor performance. It was observed that the system motion results in variations in the load, but these variations are not critical, and the current simulation tools capture the physics properly. Interestingly, variations in the rotor speed or the blade pitch angle can have a larger impact than the system motion itself.
Feng Guo, David Schlipf, and Po Wen Cheng
Wind Energ. Sci., 8, 149–171, https://doi.org/10.5194/wes-8-149-2023, https://doi.org/10.5194/wes-8-149-2023, 2023
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The benefits of lidar-assisted control are evaluated using both the Mann model and Kaimal model-based 4D turbulence, considering the variation of turbulence parameters. Simulations are performed for the above-rated mean wind speed, using the NREL 5.0 MW reference wind turbine and a four-beam lidar system. Using lidar-assisted control reduces the variations in rotor speed, pitch rate, tower base fore–aft bending moment, and electrical power significantly.
Yiyin Chen, Feng Guo, David Schlipf, and Po Wen Cheng
Wind Energ. Sci., 7, 539–558, https://doi.org/10.5194/wes-7-539-2022, https://doi.org/10.5194/wes-7-539-2022, 2022
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Lidar-assisted control of wind turbines requires a wind field generator capable of simulating wind evolution. Out of this need, we extend the Veers method for 3D wind field generation to 4D and propose a two-step Cholesky decomposition approach. Based on this, we develop a 4D wind field generator – evoTurb – coupled with TurbSim and Mann turbulence generator. We further investigate the impacts of the spatial discretization in 4D wind fields on lidar simulations to provide practical suggestions.
Vasilis Pettas, Matthias Kretschmer, Andrew Clifton, and Po Wen Cheng
Wind Energ. Sci., 6, 1455–1472, https://doi.org/10.5194/wes-6-1455-2021, https://doi.org/10.5194/wes-6-1455-2021, 2021
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This study aims to quantify the effect of inter-farm interactions based on long-term measurement data from the Alpha Ventus (AV) wind farm and the nearby FINO1 platform. AV was initially the only operating farm in the area, but in subsequent years several farms were built around it. This setup allows us to quantify the farm wake effects on the microclimate of AV and also on turbine loads and operational characteristics depending on the distance and size of the neighboring farms.
Matthias Kretschmer, Jason Jonkman, Vasilis Pettas, and Po Wen Cheng
Wind Energ. Sci., 6, 1247–1262, https://doi.org/10.5194/wes-6-1247-2021, https://doi.org/10.5194/wes-6-1247-2021, 2021
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We perform a validation of the new simulation tool FAST.Farm for the prediction of power output and structural loads in single wake conditions with respect to measurement data from the offshore wind farm alpha ventus. With a new wake-added turbulence functionality added to FAST.Farm, good agreement between simulations and measurements is achieved for the considered quantities. We hereby give insights into load characteristics of an offshore wind turbine subjected to single wake conditions.
Yiyin Chen, David Schlipf, and Po Wen Cheng
Wind Energ. Sci., 6, 61–91, https://doi.org/10.5194/wes-6-61-2021, https://doi.org/10.5194/wes-6-61-2021, 2021
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Wind evolution is currently of high interest, mainly due to the development of lidar-assisted wind turbine control (LAC). Moreover, 4D stochastic wind field simulations can be made possible by integrating wind evolution into 3D simulations to provide a more realistic simulation environment for LAC. Motivated by these factors, we investigate the potential of Gaussian process regression in the parameterization of a two-parameter wind evolution model using data of two nacelle-mounted lidars.
Martin Hofsäß, Dominique Bergmann, Jan Denzel, and Po Wen Cheng
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2019-81, https://doi.org/10.5194/wes-2019-81, 2019
Revised manuscript not accepted
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We needed a way to measure wind vectors and turbulence in complex, hard-to-access terrain. We equipped a model helicopter with a standard 3-D ultrasonic anemometer. Due to the hovering capabilities, stationary point measurements are possible. The first measurements were made in flat terrain. A 100 m high stationary wind measuring mast served as reference. The results were investigated in the time domain as well as in the frequency domain.
Steffen Raach, Bart Doekemeijer, Sjoerd Boersma, Jan-Willem van Wingerden, and Po Wen Cheng
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2019-54, https://doi.org/10.5194/wes-2019-54, 2019
Publication in WES not foreseen
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The presented work combines two control approaches of wake redirection control, feedforward wake redirection and feedback wake redirction. In our previous investigatins the lidar-assisted feedback control was studied and the advantages and disadvantages were discussed. The optimal yaw angles for the wind turbines are precomputed, the feedback takes care of uncertainties and disturbances. The concept is demonstrated in a high fidelity simulation model.
Kolja Müller and Po Wen Cheng
Wind Energ. Sci., 3, 149–162, https://doi.org/10.5194/wes-3-149-2018, https://doi.org/10.5194/wes-3-149-2018, 2018
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An efficient and accurate Monte Carlo approach is presented to assess the lifetime fatigue loading on a floating offshore wind turbine accurately. This is typically challenging in simulation effort due to the many different combinations of relevant environmental conditions which need to be considered. The applied method uses quasi-random Sobol sequences and shows promising performance with respect to convergence and accuracy.
Steffen Raach, David Schlipf, and Po Wen Cheng
Wind Energ. Sci., 2, 257–267, https://doi.org/10.5194/wes-2-257-2017, https://doi.org/10.5194/wes-2-257-2017, 2017
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This work provides a possible solution to closed-loop flow control in a wind farm.
The remote sensing technology, lidar, which is a laser-based measurement system, is used to obtain wind speed information behind a wind turbine. The measurements are processed using a model-based approach to estimate position information of the wake. The information is then used in a controller to redirect the wake to the desired position. Altogether, the concept aims to increase the power output of a wind farm.
Related subject area
Thematic area: Fluid mechanics | Topic: Wind turbine aerodynamics
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A simple vortex model applied to an idealized rotor in sheared inflow
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A comparison of dynamic inflow models for the blade element momentum method
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Model tests of a 10 MW semi-submersible floating wind turbine under waves and wind using hybrid method to integrate the rotor thrust and moments
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Shyam VimalKumar, Delphine De Tavernier, Dominic von Terzi, Marco Belloli, and Axelle Viré
Wind Energ. Sci., 9, 1967–1983, https://doi.org/10.5194/wes-9-1967-2024, https://doi.org/10.5194/wes-9-1967-2024, 2024
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When standing still without a nacelle or blades, the vibrations on a wind turbine tower are of concern to its structural health. This study finds that the air which flows around the tower recirculates behind the tower, forming so-called wakes. These wakes initiate the vibration, and the movement itself causes the vibration to increase or decrease depending on the wind speed. The current study uses a methodology called force partitioning to analyse this in depth.
Francois Trigaux, Philippe Chatelain, and Grégoire Winckelmans
Wind Energ. Sci., 9, 1765–1789, https://doi.org/10.5194/wes-9-1765-2024, https://doi.org/10.5194/wes-9-1765-2024, 2024
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In this research, the impact of blade flexibility is investigated for a very large wind turbine using numerical simulations. It is shown that bending and torsion decrease the power production and affect aerodynamic loads. Blade deformation also affects the flow of wind behind the turbine, resulting in a higher mean velocity. Our study highlights the importance of including blade flexibility in the simulation of large wind turbines to obtain accurate power and load predictions.
Erik K. Fritz, Christopher L. Kelley, and Kenneth A. Brown
Wind Energ. Sci., 9, 1713–1726, https://doi.org/10.5194/wes-9-1713-2024, https://doi.org/10.5194/wes-9-1713-2024, 2024
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This study investigates the benefits of optimizing the spacing of pressure sensors for measurement campaigns on wind turbine blades and airfoils. It is demonstrated that local aerodynamic properties can be estimated considerably more accurately when the sensor layout is optimized compared to commonly used simpler sensor layouts. This has the potential to reduce the number of sensors without losing measurement accuracy and, thus, reduce the instrumentation complexity and experiment cost.
Erik Fritz, Koen Boorsma, and Carlos Ferreira
Wind Energ. Sci., 9, 1617–1629, https://doi.org/10.5194/wes-9-1617-2024, https://doi.org/10.5194/wes-9-1617-2024, 2024
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This study presents results from a wind tunnel experiment on a model wind turbine with swept blades, thus blades curved in the rotor plane. Using a non-intrusive measurement technique, the flow around the turbine blades was measured from which blade-level aerodynamics are derived in post-processing. The detailed experimental database gives insight into swept-blade aerodynamics and has great value in validating numerical tools, which aim at simulating swept wind turbine blades.
Ricardo Fernandez-Aldama, George Papadakis, Oscar Lopez-Garcia, Sergio Avila-Sanchez, Vasilis A. Riziotis, Alvaro Cuerva-Tejero, and Cristobal Gallego-Castillo
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2024-92, https://doi.org/10.5194/wes-2024-92, 2024
Revised manuscript accepted for WES
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As longer wind turbine blades are designed, concern about vortex-induced vibrations (VIV) grows. This study identifies a new intermittent vortex shedding behaviour through a long-time simulation of a 3D wind turbine airfoil. This finding motivates a novel evaluation of airfoil vibrations at different inflow velocities. Our results show that both 2D and 3D simulations predict similar VIV characteristics during large motions, enhancing our understanding and prediction of VIV in turbine blades.
Erik Fritz, André Ribeiro, Koen Boorsma, and Carlos Ferreira
Wind Energ. Sci., 9, 1173–1187, https://doi.org/10.5194/wes-9-1173-2024, https://doi.org/10.5194/wes-9-1173-2024, 2024
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This study presents results from a wind tunnel experiment on a model wind turbine. Using a non-intrusive measurement technique, the flow around the turbine blades was measured. In post-processing, the blade-level aerodynamics are derived from the measured flow fields. The detailed experimental database has great value in validating numerical tools of varying complexity, which aim at simulating wind turbine aerodynamics as accurately as possible.
Maria Cristina Vitulano, Delphine Anne Marie De Tavernier, Giuliano De Stefano, and Dominic Alexander von Terzi
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2024-47, https://doi.org/10.5194/wes-2024-47, 2024
Revised manuscript accepted for WES
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Next-generation wind turbines are the largest rotating machines ever built, experiencing local flow Mach where the incompressibility assumption is violated, and even transonic flow can occur. This study assesses the transonic features over the FFA-W3-211 wind turbine tip airfoil for selected industrial test cases, defines the subsonic-supersonic flow threshold, and evaluates the Reynolds number effects on transonic flow occurrence. Shock wave occurrence is also depicted.
Francesco Papi, Jason Jonkman, Amy Robertson, and Alessandro Bianchini
Wind Energ. Sci., 9, 1069–1088, https://doi.org/10.5194/wes-9-1069-2024, https://doi.org/10.5194/wes-9-1069-2024, 2024
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Blade element momentum (BEM) theory is the backbone of many industry-standard aerodynamic models. However, the analysis of floating offshore wind turbines (FOWTs) introduces new challenges, which could put BEM models to the test. This study systematically compares four aerodynamic models, ranging from BEM to computational fluid dynamics, in an attempt to shed light on the unsteady aerodynamic phenomena that are at stake in FOWTs and whether BEM is able to model them appropriately.
Francesco Papi, Giancarlo Troise, Robert Behrens de Luna, Joseph Saverin, Sebastian Perez-Becker, David Marten, Marie-Laure Ducasse, and Alessandro Bianchini
Wind Energ. Sci., 9, 981–1004, https://doi.org/10.5194/wes-9-981-2024, https://doi.org/10.5194/wes-9-981-2024, 2024
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Wind turbines need to be simulated for thousands of hours to estimate design loads. Mid-fidelity numerical models are typically used for this task to strike a balance between computational cost and accuracy. The considerable displacements of floating wind turbines may be a challenge for some of these models. This paper enhances comprehension of how modeling theories affect floating wind turbine loads by comparing three codes across three turbines, simulated in a real environment.
Hye Rim Kim, Jasson A. Printezis, Jan Dominik Ahrens, Joerg R. Seume, and Lars Wein
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2024-31, https://doi.org/10.5194/wes-2024-31, 2024
Revised manuscript accepted for WES
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The need of renewable energy, so thus more efficient wind turbines, is ever increasing. Accurate prediction of the performance in the design stage is a necessary. Especially, predicting the dynamic performance of wind turbine in the region where it undergoes highly unsteady flow, is very challenging. We investigated this dynamic performance of an airfoil, which is typical for the mega-structure wind farms, to support the development of more efficient design tools in the future.
Nils Barfknecht and Dominic von Terzi
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2024-33, https://doi.org/10.5194/wes-2024-33, 2024
Revised manuscript accepted for WES
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The paper investigates the influence of the rain drop diameter on the formation of erosion damage and its implication for the erosion-safe mode (ESM). By building an erosion damage model that incorporates several drop-size effects, it is found that large droplets are significantly more erosive than small droplets. It is shown that the performance of the ESM is significantly increased when drop-size effects are correctly accounted for. A method to derive optimal ESM strategies is given as well.
Pier Francesco Melani, Omar Sherif Mohamed, Stefano Cioni, Francesco Balduzzi, and Alessandro Bianchini
Wind Energ. Sci., 9, 601–622, https://doi.org/10.5194/wes-9-601-2024, https://doi.org/10.5194/wes-9-601-2024, 2024
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The actuator line method (ALM) is a powerful tool for wind turbine simulation but struggles to resolve tip effects. The reason is still unclear. To investigate this, we use advanced angle of attack sampling and vortex tracking techniques to analyze the flow around a NACA0018 finite wing, simulated with ALM and blade-resolved computational fluid dynamics. Results show that the ALM can account for tip effects if the correct angle of attack sampling and force projection strategies are adopted.
Adhyanth Giri Ajay, Laurence Morgan, Yan Wu, David Bretos, Aurelio Cascales, Oscar Pires, and Carlos Ferreira
Wind Energ. Sci., 9, 453–470, https://doi.org/10.5194/wes-9-453-2024, https://doi.org/10.5194/wes-9-453-2024, 2024
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This paper compares six different numerical models to predict the performance of an X-shaped vertical-axis wind turbine, offering insights into how it works in 3D when its blades are fixed at specific angles. The results showed the 3D models here reliably predict the performance while still taking this turbine's complex aerodynamics into account compared to 2D models. Further, these blade angles caused more complexity in predicting the turbine's behaviour, which is highlighted in this paper.
Bruno A. Roccia, Luis R. Ceballos, Marcos L. Verstraete, and Cristian G. Gebhardt
Wind Energ. Sci., 9, 385–416, https://doi.org/10.5194/wes-9-385-2024, https://doi.org/10.5194/wes-9-385-2024, 2024
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In the literature there is a lack of meshing tools when it comes to building aerodynamic grids of wind turbines/farms to be used along with potential flow solvers. In this work, we present a detailed description of the geometric modeling and computational implementation of an interactive mesh generator, named UVLMeshGen, for onshore/offshore wind farms. The work is completed by providing a series of aerodynamic results related to wind turbines/farms to show the capacity of the mesh generator.
Federico Taruffi, Felipe Novais, and Axelle Viré
Wind Energ. Sci., 9, 343–358, https://doi.org/10.5194/wes-9-343-2024, https://doi.org/10.5194/wes-9-343-2024, 2024
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Floating wind turbines are subject to complex aerodynamics that are not yet fully understood. Lab-scale experiments are crucial for capturing these phenomena and validate numerical tools. This paper presents a new wind tunnel experimental setup able to study the response of a wind turbine rotor when subjected to prescribed motions in 6 degrees of freedom. The observed unsteady effects underscore the importance of pursuing research on the impact of floater motions on wind turbine performance.
Rishabh Mishra, Emmanuel Guilmineau, Ingrid Neunaber, and Caroline Braud
Wind Energ. Sci., 9, 235–252, https://doi.org/10.5194/wes-9-235-2024, https://doi.org/10.5194/wes-9-235-2024, 2024
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To investigate the impact of turbulence on aerodynamic forces, we first model turbulent kinetic energy decay theoretically using the Taylor length scale and employ this model to create a digital wind tunnel replica for simulating grid-generated turbulence. Experimental validation shows good alignment among theory, simulations, and experiments, paving the way for aerodynamic simulations. Finally, we successfully use the digital replica to obtain force coefficients for a 2D rotor blade section.
Leo Höning, Laura J. Lukassen, Bernhard Stoevesandt, and Iván Herráez
Wind Energ. Sci., 9, 203–218, https://doi.org/10.5194/wes-9-203-2024, https://doi.org/10.5194/wes-9-203-2024, 2024
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This study analyzes the impact of wind turbine rotor blade flexibility on the aerodynamic loading of the blades and the consequential wind characteristics in the near wake of the turbine. It is shown that gravitation leads to rotational periodic fluctuations of blade loading, which directly impacts the trajectory of the blade tip vortex at different rotor blade positions while also resulting in a non-uniform wind velocity deficit in the wake of the wind turbine.
Etienne Muller, Simone Gremmo, Félix Houtin-Mongrolle, Bastien Duboc, and Pierre Bénard
Wind Energ. Sci., 9, 25–48, https://doi.org/10.5194/wes-9-25-2024, https://doi.org/10.5194/wes-9-25-2024, 2024
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This article presents an advanced tool designed for the high-fidelity and high-performance simulation of operating wind turbines, allowing for instance the computation of a blade deformation, as well as of the surrounding airflow. As this tool relies on coupling two existing codes, the coupling strategy is first described in depth. The article then compares the code results to field data for validation.
Nils Barfknecht and Dominic von Terzi
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2023-169, https://doi.org/10.5194/wes-2023-169, 2023
Revised manuscript accepted for WES
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Rain droplets damage wind turbine blades due to the high impact speed at the tip. In this study, it is found that rain droplets and wind turbine blades interact aerodynamically. The rain droplets slow down and deform close to the blade. A model from another field of study was adapted and validated to study this process in detail. This effect reduced the predicted erosion damage by up to 50 %, primarily affecting smaller drops. It is shown how the slowdown effect can influence erosion mitigation.
Helge Aagaard Madsen
Wind Energ. Sci., 8, 1853–1872, https://doi.org/10.5194/wes-8-1853-2023, https://doi.org/10.5194/wes-8-1853-2023, 2023
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We present a linear analytical solution for a two-dimensional (2-D) actuator disc (AD) for a plane disc, a yawed disc and a coned disc. Comparisons of the 2-D model with three-dimensional computational fluid dynamics (CFD) AD simulations for a circular yawed disc and with an axis-symmetric CFD simulation of a coned disc show good correlation for the normal velocity component of the disc. This indicates that the 2-D AD model could form the basis for a consistent, simple new rotor induction model.
Stefano Cioni, Francesco Papi, Leonardo Pagamonci, Alessandro Bianchini, Néstor Ramos-García, Georg Pirrung, Rémi Corniglion, Anaïs Lovera, Josean Galván, Ronan Boisard, Alessandro Fontanella, Paolo Schito, Alberto Zasso, Marco Belloli, Andrea Sanvito, Giacomo Persico, Lijun Zhang, Ye Li, Yarong Zhou, Simone Mancini, Koen Boorsma, Ricardo Amaral, Axelle Viré, Christian W. Schulz, Stefan Netzband, Rodrigo Soto-Valle, David Marten, Raquel Martín-San-Román, Pau Trubat, Climent Molins, Roger Bergua, Emmanuel Branlard, Jason Jonkman, and Amy Robertson
Wind Energ. Sci., 8, 1659–1691, https://doi.org/10.5194/wes-8-1659-2023, https://doi.org/10.5194/wes-8-1659-2023, 2023
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Simulations of different fidelities made by the participants of the OC6 project Phase III are compared to wind tunnel wake measurements on a floating wind turbine. Results in the near wake confirm that simulations and experiments tend to diverge from the expected linearized quasi-steady behavior when the reduced frequency exceeds 0.5. In the far wake, the impact of platform motion is overestimated by simulations and even seems to be oriented to the generation of a wake less prone to dissipation.
Christian Grinderslev, Felix Houtin-Mongrolle, Niels Nørmark Sørensen, Georg Raimund Pirrung, Pim Jacobs, Aqeel Ahmed, and Bastien Duboc
Wind Energ. Sci., 8, 1625–1638, https://doi.org/10.5194/wes-8-1625-2023, https://doi.org/10.5194/wes-8-1625-2023, 2023
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In standstill conditions wind turbines are at risk of vortex-induced vibrations (VIVs). VIVs can become large and lead to significant fatigue of the wind turbine structure over time. Thus it is important to have tools that can accurately compute this complex phenomenon. This paper studies the sensitivities to the chosen models of computational fluid dynamics (CFD) simulations when modelling VIVs and finds that much care is needed when setting up simulations, especially for specific flow angles.
Mohammad Rasoul Tirandaz, Abdolrahim Rezaeiha, and Daniel Micallef
Wind Energ. Sci., 8, 1403–1424, https://doi.org/10.5194/wes-8-1403-2023, https://doi.org/10.5194/wes-8-1403-2023, 2023
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Vertical axis wind turbines experience a variation of torque and power throughout their rotation. Traditional non-morphing blades are intrinsically not able to respond to this variation, resulting in a turbine which has suboptimal performance. In principle, it is possible to have a morphing blade that adapts to the blade's rotation and changes its geometry in such a way as to optimise the performance of the turbine. This paper addresses the question of how such blade should morph as it rotates.
Ferdinand Seel, Thorsten Lutz, and Ewald Krämer
Wind Energ. Sci., 8, 1369–1385, https://doi.org/10.5194/wes-8-1369-2023, https://doi.org/10.5194/wes-8-1369-2023, 2023
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Vortex generators are evaluated on a 2 MW wind turbine rotor blade by computational fluid dynamic methods. Those devices delay flow separation on the airfoils and thus increase their efficiency. On the wind turbine blade, rotational phenomena (e.g. rotational augmentation) appear and interact with the vortices from the vortex generators. The understanding of those interactions is crucial in order to optimise the placement of the vortex generators and evaluate their real efficiency on the blade.
Jens N. Sørensen
Wind Energ. Sci., 8, 1017–1027, https://doi.org/10.5194/wes-8-1017-2023, https://doi.org/10.5194/wes-8-1017-2023, 2023
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The paper presents a simple analytical model that, with surprisingly good accuracy, represents the loading for virtually any horizontal axis wind turbine, independent of size and operating regime. The aim of the model is to have a simple tool that may represent the loading of any wind turbine without having access to the details regarding the specific geometry and airfoil data, information that is normally kept confidential by the manufacturer of the turbine.
André F. P. Ribeiro, Damiano Casalino, and Carlos S. Ferreira
Wind Energ. Sci., 8, 661–675, https://doi.org/10.5194/wes-8-661-2023, https://doi.org/10.5194/wes-8-661-2023, 2023
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Floating offshore wind turbines move due to not having a rigid foundation. Hence, as the blades rotate they experience more complex aerodynamics than standard onshore wind turbines. In this paper, we show computational simulations of a wind turbine rotor moving in various ways and quantify the effects of the motion in the forces acting on the blades. We show that these forces behave in nonlinear ways in some cases.
Roger Bergua, Amy Robertson, Jason Jonkman, Emmanuel Branlard, Alessandro Fontanella, Marco Belloli, Paolo Schito, Alberto Zasso, Giacomo Persico, Andrea Sanvito, Ervin Amet, Cédric Brun, Guillén Campaña-Alonso, Raquel Martín-San-Román, Ruolin Cai, Jifeng Cai, Quan Qian, Wen Maoshi, Alec Beardsell, Georg Pirrung, Néstor Ramos-García, Wei Shi, Jie Fu, Rémi Corniglion, Anaïs Lovera, Josean Galván, Tor Anders Nygaard, Carlos Renan dos Santos, Philippe Gilbert, Pierre-Antoine Joulin, Frédéric Blondel, Eelco Frickel, Peng Chen, Zhiqiang Hu, Ronan Boisard, Kutay Yilmazlar, Alessandro Croce, Violette Harnois, Lijun Zhang, Ye Li, Ander Aristondo, Iñigo Mendikoa Alonso, Simone Mancini, Koen Boorsma, Feike Savenije, David Marten, Rodrigo Soto-Valle, Christian W. Schulz, Stefan Netzband, Alessandro Bianchini, Francesco Papi, Stefano Cioni, Pau Trubat, Daniel Alarcon, Climent Molins, Marion Cormier, Konstantin Brüker, Thorsten Lutz, Qing Xiao, Zhongsheng Deng, Florence Haudin, and Akhilesh Goveas
Wind Energ. Sci., 8, 465–485, https://doi.org/10.5194/wes-8-465-2023, https://doi.org/10.5194/wes-8-465-2023, 2023
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This work examines if the motion experienced by an offshore floating wind turbine can significantly affect the rotor performance. It was observed that the system motion results in variations in the load, but these variations are not critical, and the current simulation tools capture the physics properly. Interestingly, variations in the rotor speed or the blade pitch angle can have a larger impact than the system motion itself.
Mac Gaunaa, Niels Troldborg, and Emmanuel Branlard
Wind Energ. Sci., 8, 503–513, https://doi.org/10.5194/wes-8-503-2023, https://doi.org/10.5194/wes-8-503-2023, 2023
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We present an analytical vortex model. Despite its simplicity, the model is fully consistent with 1D momentum theory. It shows that the flow through a non-uniformly loaded rotor operating in non-uniform inflow behaves locally as predicted by 1D momentum theory. As a consequence, the local power coefficient (based on local inflow) of an ideal rotor is unaltered by the presence of shear. Finally, the model shows that there is no cross-shear deflection of the wake of a rotor in sheared inflow.
Kelsey Shaler, Benjamin Anderson, Luis A. Martínez-Tossas, Emmanuel Branlard, and Nick Johnson
Wind Energ. Sci., 8, 383–399, https://doi.org/10.5194/wes-8-383-2023, https://doi.org/10.5194/wes-8-383-2023, 2023
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Free-vortex wake (OLAF) and low-fidelity blade-element momentum (BEM) structural results are compared to high-fidelity simulation results for a flexible downwind turbine for varying inflow conditions. Overall, OLAF results were more consistent than BEM results when compared to SOWFA results under challenging inflow conditions. Differences between OLAF and BEM results were dominated by yaw misalignment angle, with varying shear exponent and turbulence intensity causing more subtle differences.
Francesco Caccia and Alberto Guardone
Wind Energ. Sci., 8, 341–362, https://doi.org/10.5194/wes-8-341-2023, https://doi.org/10.5194/wes-8-341-2023, 2023
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Ice roughness deteriorates wind turbine aerodynamics. We have shown numerically that this also occurs when complex ice shapes are present on the leading edge, as long as the blade's wet region extends beyond the ice shape itself and roughness elements are high enough. Such features are typical of icing events on wind turbines but are not captured by current icing simulation tools. Future research should focus on correctly computing both the wet region of the blade and the roughness height.
Koen Boorsma, Gerard Schepers, Helge Aagard Madsen, Georg Pirrung, Niels Sørensen, Galih Bangga, Manfred Imiela, Christian Grinderslev, Alexander Meyer Forsting, Wen Zhong Shen, Alessandro Croce, Stefano Cacciola, Alois Peter Schaffarczyk, Brandon Lobo, Frederic Blondel, Philippe Gilbert, Ronan Boisard, Leo Höning, Luca Greco, Claudio Testa, Emmanuel Branlard, Jason Jonkman, and Ganesh Vijayakumar
Wind Energ. Sci., 8, 211–230, https://doi.org/10.5194/wes-8-211-2023, https://doi.org/10.5194/wes-8-211-2023, 2023
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Within the framework of the fourth phase of the International Energy Agency's (IEA) Wind Task 29, a large comparison exercise between measurements and aeroelastic simulations has been carried out. Results were obtained from more than 19 simulation tools of various fidelity, originating from 12 institutes and compared to state-of-the-art field measurements. The result is a unique insight into the current status and accuracy of rotor aerodynamic modeling.
Simone Mancini, Koen Boorsma, Gerard Schepers, and Feike Savenije
Wind Energ. Sci., 8, 193–210, https://doi.org/10.5194/wes-8-193-2023, https://doi.org/10.5194/wes-8-193-2023, 2023
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Modern wind turbines are subject to complex wind conditions that are far from the hypothesis of steady uniform inflow at the core of blade element momentum methods (the current industry standard for wind turbine design). Various corrections have been proposed to model this complexity. The present work focuses on modelling the unsteady evolution of wind turbine wakes (dynamic inflow), comparing the different corrections available and highlighting their effects on design load predictions.
Christian Grinderslev, Niels Nørmark Sørensen, Georg Raimund Pirrung, and Sergio González Horcas
Wind Energ. Sci., 7, 2201–2213, https://doi.org/10.5194/wes-7-2201-2022, https://doi.org/10.5194/wes-7-2201-2022, 2022
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As wind turbines increase in size, the risk of flow-induced instabilities increases. This study investigates the phenomenon of vortex-induced vibrations (VIVs) on a large 10 MW wind turbine blade using two high-fidelity methods. It is found that VIVs can occur with multiple equilibrium states for the same flow case, showing an dependence on the initial conditions. This means that a blade which is stable in a flow can become unstable if, e.g., a turbine operation provokes an initial vibration.
Felipe Vittori, José Azcona, Irene Eguinoa, Oscar Pires, Alberto Rodríguez, Álex Morató, Carlos Garrido, and Cian Desmond
Wind Energ. Sci., 7, 2149–2161, https://doi.org/10.5194/wes-7-2149-2022, https://doi.org/10.5194/wes-7-2149-2022, 2022
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This paper describes the results of a wave tank test campaign of a scaled SATH 10 MW INNWIND floating platform. The software-in-the-loop (SiL) hybrid method was used to include the wind turbine thrust and the in-plane rotor moments. Experimental results are compared with a numerical model developed in OpenFAST of the floating wind turbine. The results are discussed, identifying limitations of the numerical models and obtaining conclusions on how to improve them.
Thanasis Barlas, Georg Raimund Pirrung, Néstor Ramos-García, Sergio González Horcas, Ang Li, and Helge Aagaard Madsen
Wind Energ. Sci., 7, 1957–1973, https://doi.org/10.5194/wes-7-1957-2022, https://doi.org/10.5194/wes-7-1957-2022, 2022
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An aeroelastically optimized curved wind turbine blade tip is designed, manufactured, and tested on a novel outdoor rotating rig facility at the Risø campus of the Technical University of Denmark. Detailed aerodynamic measurements for various atmospheric conditions and results are compared to a series of in-house aeroelastic tools with a range of fidelities in aerodynamic modeling. The comparison highlights details in the ability of the codes to predict the performance of such a curved tip.
Jan-Philipp Küppers and Tamara Reinicke
Wind Energ. Sci., 7, 1889–1903, https://doi.org/10.5194/wes-7-1889-2022, https://doi.org/10.5194/wes-7-1889-2022, 2022
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Airfoils play a major role in the technical harnessing of energy from currents such as wind and water. When the angle of attack of a wing changes dynamically, the forces on the wing often change more than would have been assumed from static measurements alone. Since these dynamic forces have a strong influence, e.g., on the performance of airplanes and wind turbines, a neural-network-based model was created that can predict these loads and their stochastic fluctuations.
Frederik Berger, Lars Neuhaus, David Onnen, Michael Hölling, Gerard Schepers, and Martin Kühn
Wind Energ. Sci., 7, 1827–1846, https://doi.org/10.5194/wes-7-1827-2022, https://doi.org/10.5194/wes-7-1827-2022, 2022
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We proof the dynamic inflow effect due to gusts in wind tunnel experiments with MoWiTO 1.8 in the large wind tunnel of ForWind – University of Oldenburg, where we created coherent gusts with an active grid. The effect is isolated in loads and rotor flow by comparison of a quasi-steady and a dynamic case. The observed effect is not caught by common dynamic inflow engineering models. An improvement to the Øye dynamic inflow model is proposed, matching experiment and corresponding FVWM simulations.
Thomas Potentier, Emmanuel Guilmineau, Arthur Finez, Colin Le Bourdat, and Caroline Braud
Wind Energ. Sci., 7, 1771–1790, https://doi.org/10.5194/wes-7-1771-2022, https://doi.org/10.5194/wes-7-1771-2022, 2022
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A wind turbine blade equipped with root spoilers is analysed using time domain aeroelastic simulations to assess the impact of passive devices on the turbine AEP and lifetime. A novel way to account for aerofoil-generated unsteadiness in the fatigue calculation is proposed and detailed. The outcome shows that spoilers, on average, can increase the AEP of the turbine. However, the structural impacts on the turbine can be severe if not accounted for initially in the turbine design.
Alessandro Fontanella, Alan Facchinetti, Simone Di Carlo, and Marco Belloli
Wind Energ. Sci., 7, 1711–1729, https://doi.org/10.5194/wes-7-1711-2022, https://doi.org/10.5194/wes-7-1711-2022, 2022
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The aerodynamics of floating wind turbines is complicated by large motions permitted by the foundation. The interaction between turbine, wind, and wake is not yet fully understood. The wind tunnel experiments of this paper shed light on the aerodynamic force and wake response of the floating IEA 15 MW turbine subjected to platform motion as would occur during normal operation. This will help future research on turbine and wind farm control.
Emmanouil M. Nanos, Carlo L. Bottasso, Simone Tamaro, Dimitris I. Manolas, and Vasilis A. Riziotis
Wind Energ. Sci., 7, 1641–1660, https://doi.org/10.5194/wes-7-1641-2022, https://doi.org/10.5194/wes-7-1641-2022, 2022
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A novel way of wind farm control is presented where the wake is deflected vertically to reduce interactions with downstream turbines. This is achieved by moving ballast in a floating offshore platform in order to pitch the support structure and thereby tilt the wind turbine rotor disk. The study considers the effects of this new form of wake control on the aerodynamics of the steering and wake-affected turbines, on the structure, and on the ballast motion system.
Giorgia Guma, Philipp Bucher, Patrick Letzgus, Thorsten Lutz, and Roland Wüchner
Wind Energ. Sci., 7, 1421–1439, https://doi.org/10.5194/wes-7-1421-2022, https://doi.org/10.5194/wes-7-1421-2022, 2022
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Wind turbine aeroelasticity is becoming more and more important because turbine sizes are increasingly leading to more slender blades. On the other hand, complex terrains are of interest because they are far away from urban areas. These regions are characterized by low velocities and high turbulence and are mostly influenced by the presence of forest, and that is why it is necessary to develop high-fidelity tools to correctly simulate the wind turbine's response.
Sarah Barber, Julien Deparday, Yuriy Marykovskiy, Eleni Chatzi, Imad Abdallah, Gregory Duthé, Michele Magno, Tommaso Polonelli, Raphael Fischer, and Hanna Müller
Wind Energ. Sci., 7, 1383–1398, https://doi.org/10.5194/wes-7-1383-2022, https://doi.org/10.5194/wes-7-1383-2022, 2022
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Aerodynamic and acoustic field measurements on operating large-scale wind turbines are key for the further reduction in the costs of wind energy. In this work, a novel cost-effective MEMS (micro-electromechanical systems)-based aerodynamic and acoustic wireless measurement system that is thin, non-intrusive, easy to install, low power and self-sustaining is designed and tested.
Ang Li, Mac Gaunaa, Georg Raimund Pirrung, Alexander Meyer Forsting, and Sergio González Horcas
Wind Energ. Sci., 7, 1341–1365, https://doi.org/10.5194/wes-7-1341-2022, https://doi.org/10.5194/wes-7-1341-2022, 2022
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A consistent method of using two-dimensional airfoil data when using generalized lifting-line methods for the aerodynamic load calculation of non-planar horizontal-axis wind turbines is described. The important conclusions from the unsteady two-dimensional airfoil aerodynamics are highlighted. The impact of using a simplified approach instead of using the full model on the prediction of the aerodynamic performance of non-planar rotors is shown numerically for different aerodynamic models.
Cited articles
Bauer, M. and Abdel-Maksoud, M.: A 3-D Potential Based Boundary Element Method for Modelling and Simulation of Marine Propeller Flows, in: IFAC Proceedings Volumes, vol. 45 of 7th Vienna International Conference on Mathematical Modelling, Elsevier, 1179–1184, https://doi.org/10.3182/20120215-3-AT-3016.00209, 2012. a
Bayati, I., Belloli, M., Bernini, L., and Zasso, A.: Wind tunnel validation of AeroDyn within LIFES50+ project: imposed Surge and Pitch tests, J. Phys.: Conf. Ser., 753, 092001, https://doi.org/10.1088/1742-6596/753/9/092001, 2016. a, b
Bayati, I., Belloli, M., Bernini, L., Boldrin, D., Boorsma, K., Caboni, M., Cormier, M., Mikkelsen, R., Lutz, T., and Zasso, A.: UNAFLOW project: UNsteady Aerodynamics of FLOating Wind turbines, J. Phys.: Conf. Ser., 1037, 072037, https://doi.org/10.1088/1742-6596/1037/7/072037, 2018. a, b
Bergua, R., Robertson, A., Jonkman, J., Branlard, E., Fontanella, A., Belloli, M., Schito, P., Zasso, A., Persico, G., Sanvito, A., Amet, E., Brun, C., Campaña-Alonso, G., Martín-San-Román, R., Cai, R., Cai, J., Qian, Q., Maoshi, W., Beardsell, A., Pirrung, G., Ramos-García, N., Shi, W., Fu, J., Corniglion, R., Lovera, A., Galván, J., Nygaard, T. A., dos Santos, C. R., Gilbert, P., Joulin, P.-A., Blondel, F., Frickel, E., Chen, P., Hu, Z., Boisard, R., Yilmazlar, K., Croce, A., Harnois, V., Zhang, L., Li, Y., Aristondo, A., Mendikoa Alonso, I., Mancini, S., Boorsma, K., Savenije, F., Marten, D., Soto-Valle, R., Schulz, C. W., Netzband, S., Bianchini, A., Papi, F., Cioni, S., Trubat, P., Alarcon, D., Molins, C., Cormier, M., Brüker, K., Lutz, T., Xiao, Q., Deng, Z., Haudin, F., and Goveas, A.: OC6 project Phase III: validation of the aerodynamic loading on a wind turbine rotor undergoing large motion caused by a floating support structure, Wind Energy. Sci., 8, 465–485, https://doi.org/10.5194/wes-8-465-2023, 2023. a, b, c, d, e
Branlard, E., Brownstein, I., Strom, B., Jonkman, J., Dana, S., and Baring-Gould, E. I.: A multipurpose lifting-line flow solver for arbitrary wind energy concepts, Wind Energ Sci, 7, 455–467, https://doi.org/10.5194/wes-7-455-2022, 2022a. a
Branlard, E., Jonkman, B., Pirrung, G. R., Dixon, K., and Jonkman, J.: Dynamic inflow and unsteady aerodynamics models for modal and stability analyses in OpenFAST, J. Phys.: Conf. Ser., 2265, 032044, https://doi.org/10.1088/1742-6596/2265/3/032044, 2022b. a, b
Chen, Z., Wang, X., and Kang, S.: Effect of the Coupled Pitch–Yaw Motion on the Unsteady Aerodynamic Performance and Structural Response of a Floating Offshore Wind Turbine, Processes, 9, 290, https://doi.org/10.3390/pr9020290, 2021. a, b
Cormier, M., Caboni, M., Lutz, T., Boorsma, K., and Krämer, E.: Numerical analysis of unsteady aerodynamics of floating offshore wind turbines, J. Phys.: Conf. Ser., 1037, 072048, https://doi.org/10.1088/1742-6596/1037/7/072048, 2018. a
Damiani, R. R. and Hayman, G.: The Unsteady Aerodynamics Module For FAST8, Tech. Rep. NREL/TP–5000-66347, 1576488, NREL – National Renewable Energy Lab., Golden, CO, USA, https://doi.org/10.2172/1576488, 2019. a
de Vaal, J., Hansen, M. L., and Moan, T.: Effect of wind turbine surge motion on rotor thrust and induced velocity, Wind Energy, 17, 105–121, https://doi.org/10.1002/we.1562, 2014. a
Drela, M.: XFOIL: An Analysis and Design System for Low Reynolds Number Airfoils, in: Low Reynolds Number Aerodynamics, Lecture Notes in Engineering, edited by: Mueller, T. J., Springer, 1–12, ISBN 978-3-642-84010-4, https://doi.org/10.1007/978-3-642-84010-4_1, 1989. a
Fang, Y., Duan, L., Han, Z., Zhao, Y., and Yang, H.: Numerical analysis of aerodynamic performance of a floating offshore wind turbine under pitch motion, Energy, 192, 116621, https://doi.org/10.1016/j.energy.2019.116621, 2020. a
Farrugia, R., Sant, T., and Micallef, D.: Investigating the aerodynamic performance of a model offshore floating wind turbine, Renew. Energy, 70, 24–30, https://doi.org/10.1016/j.renene.2013.12.043, 2014. a, b, c
Farrugia, R., Sant, T., and Micallef, D.: A study on the aerodynamics of a floating wind turbine rotor, Renew. Energy, 86, 770–784, https://doi.org/10.1016/j.renene.2015.08.063, 2015. a, b
Ferreira, C., Yu, W., Sala, A., and Viré, A.: Dynamic inflow model for a floating horizontal axis wind turbine in surge motion, Wind Energ. Sci., 7, 469–485, https://doi.org/10.5194/wes-7-469-2022, 2022. a
Fontanella, A., Bayati, I., Mikkelsen, R., Belloli, M., and Zasso, A.: UNAFLOW: a holistic wind tunnel experiment about the aerodynamic response of floating wind turbines under imposed surge motion, Wind Energ. Sci., 6, 1169–1190, https://doi.org/10.5194/wes-6-1169-2021, 2021. a, b, c, d
Fontanella, A., Facchinetti, A., Di Carlo, S., and Belloli, M.: Wind tunnel investigation of the aerodynamic response of two 15 MW floating wind turbines, Wind Energ. Sci., 7, 1711–1729, https://doi.org/10.5194/wes-7-1711-2022, 2022. a, b, c
Fontanella, A., Daka, E., Novais, F., and Belloli, M.: Aerodynamic response of a floating wind turbine scale model with inclusion of reference control functionalities, Wind Energ. Sci. [preprint], https://doi.org/10.5194/wes-2023-29, 2023. a, b, c, d
Gaertner, E., Rinker, J., Sethuraman, L., Zahle, F., Anderson, B., Barter, G. E., Abbas, N. J., Meng, F., Bortolotti, P., Skrzypinski, W., Scott, G. N., Feil, R., Bredmose, H., Dykes, K., Shields, M., Allen, C., and Viselli, A.: IEA Wind TCP Task 37: Definition of the IEA 15-Megawatt Offshore Reference Wind Turbine, Tech. Rep. NREL/TP-5000-75698, NREL – National Renewable Energy Lab., Golden, CO, USA, https://doi.org/10.2172/1603478, 2020. a
Jonkman, B. Mudafort, R. M., Platt, A., Branlard, E., Sprague, M., Jonkman, J., HaymanConsulting, Vijayakumar, G., Buhl, M., Ross, H., Bortolotti, P., Masciola, M., Ananthan, S., Schmidt, M. J., Rood, J., rdamiani, nrmendoza, sinolonghai, Hall, M., …, and rcorniglion: OpenFAST/openfast: OpenFAST v3.1.0, Zenodo [code], https://doi.org/10.5281/zenodo.6324288, 2022. a, b
Leishman, J. G.: Challenges in modelling the unsteady aerodynamics of wind turbines, Wind Energy, 5, 85–132, https://doi.org/10.1002/we.62, 2002. a
Leishman, J. G. and Beddoes, T. S.: A Semi-Empirical Model for Dynamic Stall, J. Am. Helicopt. Soc., 34, 3–17, https://doi.org/10.4050/JAHS.34.3.3, 1989. a, b
Lienard, C., Boisard, R., and Daudin, C.: Aerodynamic Behavior of a Floating Offshore Wind Turbine, AIAA J., 58, 3835–3847, https://doi.org/10.2514/1.J059255, 2020. a, b
Loewy, R. G.: A Two-Dimensional Approximation to the Unsteady Aerodynamics of Rotary Wings, J. Aeronaut. Sci., 24, 81–92, https://doi.org/10.2514/8.3777, 1957. a
Lyon, C. A., Broeren, A. P., Giguere, P., Gopalarathnam, A., and Selig, M. S.: Summary of Low-Speed Airfoil Data, in: Volume 3, Tech. rep., SoarTech Publications, University of Illinois, ISBN 0-9646747-3-4, 1997. a
Mancini, S., Boorsma, K., Caboni, M., Cormier, M., Lutz, T., Schito, P., and Zasso, A.: Characterization of the unsteady aerodynamic response of a floating offshore wind turbine to surge motion, Wind Energ. Sci., 5, 1713–1730, https://doi.org/10.5194/wes-5-1713-2020, 2020. a, b, c, d, e, f, g, h, i, j
Mancini, S., Boorsma, K., Caboni, M., Hermans, K., and Savenije, F.: An engineering modification to the blade element momentum method for floating wind turbines, J. Phys.: Conf. Ser., 2265, 042017, https://doi.org/10.1088/1742-6596/2265/4/042017, 2022. a
Meng, H., Su, H., Guo, J., Qu, T., and Lei, L.: Experimental investigation on the power and thrust characteristics of a wind turbine model subjected to surge and sway motions, Renew. Energy, 181, 1325–1337, https://doi.org/10.1016/j.renene.2021.10.003, 2022. a, b
Micallef, D. and Sant, T.: Loading effects on floating offshore horizontal axis wind turbines in surge motion, Renew. Energy, 83, 737–748, https://doi.org/10.1016/j.renene.2015.05.016, 2015. a
Moriarty, P. J. and Hansen, A. C.: AeroDyn Theory Manual, Tech. Rep. NREL/T-500-36881, National Renewable Energy Lab., Golden, CO, USA, https://doi.org/10.2172/15014831, 2005. a
Netzband, S., Schulz, C. W., Göttsche, U., Ferreira González, D., and Abdel-Maksoud, M.: A panel method for floating offshore wind turbine simulations with fully integrated aero- and hydrodynamic modelling in time domain, Ship. Technol. Res., 65, 123–136, https://doi.org/10.1080/09377255.2018.1475710, 2018. a, b, c
Netzband, S., Schulz, C. W., and Abdel-Maksoud, M.: Self-aligning behaviour of a passively yawing floating offshore wind turbine, Ship. Technol. Res., 67, 15–25, https://doi.org/10.1080/09377255.2018.1555986, 2020. a
Netzband, S., Schulz, C. W., Özinan, U., Adam, R., Choisnet, T., Cheng, P. W., and Abdel-Maksoud, M.: Validation of a panel method with full-scale FOWT measurements and verification with engineering models, J. Phys.: Conf. Ser., 2626, 012061, https://doi.org/10.1088/1742-6596/2626/1/012061, 2023. a
Ramos-García, N., Sørensen, J. N., and Shen, W. Z.: Three-dimensional viscous-inviscid coupling method for wind turbine computations, Wind Energy, 19, 67–93, https://doi.org/10.1002/we.1821, 2016. a
Roura, M., Cuerva, A., Sanz-Andrés, A., and Barrero-Gil, A.: A panel method free-wake code for aeroelastic rotor predictions, Wind Energy, 13, 357–371, https://doi.org/10.1002/we.358, 2010. a
Sant, T. and Cuschieri, K.: Comparing Three Aerodynamic Models for Predicting the Thrust and Power Characteristics of a Yawed Floating Wind Turbine Rotor, J. Sol. Energ. Eng., 138, 031004, https://doi.org/10.1115/1.4032684, 2016. a
Sant, T., Bonnici, D., Farrugia, R., and Micallef, D.: Measurements and modelling of the power performance of a model floating wind turbine under controlled conditions, Wind Energy, 18, 811–834, https://doi.org/10.1002/we.1730, 2015. a, b
Schulz, C. W., Wang, K., Wieczorek, K., Netzband, S., and Abdel-Maksoud, M.: Experimental and numerical investigation of the yaw moment of a downwind coned wind turbine rotor, Wind Energy, 25, 1995–2015, https://doi.org/10.1002/we.2779, 2022. a, b, c
Schulz, C. W., Özinan, U., Netzband, S., Cheng, P. W., and Abdel-Maksoud, M.: The Impact of Unsteadiness on the Aerodynamic Loads of a Floating Offshore Wind Turbine, J. Phys.: Conf. Ser., 2626, 012064, https://doi.org/10.1088/1742-6596/2626/1/012064, 2023. a, b, c, d
Sebastian, T. and Lackner, M.: Analysis of the Induction and Wake Evolution of an Offshore Floating Wind Turbine, Energies, 5, 968–1000, https://doi.org/10.3390/en5040968, 2012. a, b
Sebastian, T. and Lackner, M.: Characterization of the unsteady aerodynamics of offshore floating wind turbines, Wind Energy, 16, 339–352, https://doi.org/10.1002/we.545, 2013. a
Sivalingam, K., Martin, S., and Singapore Wala, A.: Numerical Validation of Floating Offshore Wind Turbine Scaled Rotors for Surge Motion, Energies, 11, 2578, https://doi.org/10.3390/en11102578, 2018. a, b
Snel, H., Schepers, J. G., van Bussel, G. J. W., Vermeer, L. J., Rawlinson Smith, R. I., Voutsinas, S., van Holten, T., Oye, S., and Bareiß, R.: Joint investigation of dynamic inflow effects and implementation of an engineering method, Tech. Rep. ECN-C-94-107, Netherlands Energy Research Center, https://publications.ecn.nl/E/1995/ECN-C--94-107 (last access: 20 December 2023), 1995. a
Tran, T. T. and Kim, D.-H.: The platform pitching motion of floating offshore wind turbine: A preliminary unsteady aerodynamic analysis, Renew. Energy, 142, 65–81, https://doi.org/10.1016/j.jweia.2015.03.009, 2015. a
Tran, T. T., Kim, D.-H., and Hieu Nguyen, B.: Aerodynamic Interference Effect of Huge Wind Turbine Blades With Periodic Surge Motions Using Overset Grid-Based Computational Fluid Dynamics Approach, J. Sol. Energ. Eng., 137, 061003, https://doi.org/10.1115/1.4031184, 2015. a, b, c
van Garrel, A.: Multilevel panel method for wind turbine rotor flow simulations, phdthesis, University of Twente, ISBN 9789036542241, https://doi.org/10.3990/1.9789036542241, 2016. a
Wang, Y. and Abdel-Maksoud, M.: Coupling wake alignment lifting line method and boundary element method for open water and unsteady propeller simulation, Ocean Eng., 213, 107738, https://doi.org/10.1016/j.oceaneng.2020.107738, 2020. a
Wei, N. J. and Dabiri, J. O.: Phase-averaged dynamics of a periodically surging wind turbine, J. Renew. Sustain. Energ., 14, 013305, https://doi.org/10.1063/5.0076029, 2022. a, b
Wu, C.-H. K. and Nguyen, V.-T.: Aerodynamic simulations of offshore floating wind turbine in platform-induced pitching motion: Numerical simulations of FOWT in coupled motions, Wind Energy, 20, 835–858, https://doi.org/10.1002/we.2066, 2017. a
Short summary
Understanding the underlying physical phenomena of the aerodynamics of floating offshore wind turbines (FOWTs) is crucial for successful simulations. No consensus has been reached in the research community on which unsteady aerodynamic phenomena are relevant and how much they can influence the loads acting on a FOWT. This work contributes to the understanding and characterisation of such unsteady phenomena using a novel experimental approach and comprehensive numerical investigations.
Understanding the underlying physical phenomena of the aerodynamics of floating offshore wind...
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