Articles | Volume 8, issue 5
https://doi.org/10.5194/wes-8-819-2023
© Author(s) 2023. 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-8-819-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
26 May 2023
Research article |
| 26 May 2023
| 26 May 2023
A new RANS-based wind farm parameterization and inflow model for wind farm cluster modeling
DTU Wind and Energy Systems, Technical University of Denmark, Risø Campus, Frederiksborgvej 399, 4000 Roskilde, Denmark
Oscar García-Santiago
DTU Wind and Energy Systems, Technical University of Denmark, Risø Campus, Frederiksborgvej 399, 4000 Roskilde, Denmark
Mark Kelly
DTU Wind and Energy Systems, Technical University of Denmark, Risø Campus, Frederiksborgvej 399, 4000 Roskilde, Denmark
Alexander Meyer Forsting
DTU Wind and Energy Systems, Technical University of Denmark, Risø Campus, Frederiksborgvej 399, 4000 Roskilde, Denmark
Camille Dubreuil-Boisclair
Equinor ASA, Oslo, Norway
Knut Sponheim Seim
Equinor ASA, Oslo, Norway
Marc Imberger
DTU Wind and Energy Systems, Technical University of Denmark, Risø Campus, Frederiksborgvej 399, 4000 Roskilde, Denmark
Alfredo Peña
DTU Wind and Energy Systems, Technical University of Denmark, Risø Campus, Frederiksborgvej 399, 4000 Roskilde, Denmark
Niels Nørmark Sørensen
DTU Wind and Energy Systems, Technical University of Denmark, Risø Campus, Frederiksborgvej 399, 4000 Roskilde, Denmark
Pierre-Elouan Réthoré
DTU Wind and Energy Systems, Technical University of Denmark, Risø Campus, Frederiksborgvej 399, 4000 Roskilde, Denmark
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Julian Quick, Pierre-Elouan Rethore, Mads Mølgaard Pedersen, Rafael Valotta Rodrigues, and Mikkel Friis-Møller
Wind Energ. Sci., 8, 1235–1250, https://doi.org/10.5194/wes-8-1235-2023, https://doi.org/10.5194/wes-8-1235-2023, 2023
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Wei Fu, Alessandro Sebastiani, Alfredo Peña, and Jakob Mann
Wind Energ. Sci., 8, 677–690, https://doi.org/10.5194/wes-8-677-2023, https://doi.org/10.5194/wes-8-677-2023, 2023
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Camilla Marie Nyborg, Andreas Fischer, Pierre-Elouan Réthoré, and Ju Feng
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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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Xiaoli Guo Larsén, Marc Imberger, Ásta Hannesdóttir, and Andrea N. Hahmann
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2022-102, https://doi.org/10.5194/wes-2022-102, 2023
Revised manuscript not accepted
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We study how climate change will impact extreme winds and choice of turbine class. We use data from 18 CMIP6 members from a historic and a future period to access the change in the extreme winds. The analysis shows an overall increase in the extreme winds in the North Sea and the southern Baltic Sea, but a decrease over the Scandinavian Peninsula and most of the Baltic Sea. The analysis is inconclusive to whether higher or lower classes of turbines will be installed in the future.
Andrea N. Hahmann, Oscar García-Santiago, and Alfredo Peña
Wind Energ. Sci., 7, 2373–2391, https://doi.org/10.5194/wes-7-2373-2022, https://doi.org/10.5194/wes-7-2373-2022, 2022
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We explore the changes in wind energy resources in northern Europe using output from simulations from the Climate Model Intercomparison Project (CMIP6) under the high-emission scenario. Our results show that climate change does not particularly alter annual energy production in the North Sea but could affect the seasonal distribution of these resources, significantly reducing energy production during the summer from 2031 to 2050.
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.
Mads Baungaard, Stefan Wallin, Maarten Paul van der Laan, and Mark Kelly
Wind Energ. Sci., 7, 1975–2002, https://doi.org/10.5194/wes-7-1975-2022, https://doi.org/10.5194/wes-7-1975-2022, 2022
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Wind turbine wakes in the neutral atmospheric surface layer are simulated with Reynolds-averaged Navier–Stokes (RANS) using an explicit algebraic Reynolds stress model. Contrary to standard two-equation turbulence models, it can predict turbulence anisotropy and complex physical phenomena like secondary motions. For the cases considered, it improves Reynolds stress, turbulence intensity, and velocity deficit predictions, although a more top-hat-shaped profile is observed for the latter.
Tuhfe Göçmen, Filippo Campagnolo, Thomas Duc, Irene Eguinoa, Søren Juhl Andersen, Vlaho Petrović, Lejla Imširović, Robert Braunbehrens, Jaime Liew, Mads Baungaard, Maarten Paul van der Laan, Guowei Qian, Maria Aparicio-Sanchez, Rubén González-Lope, Vinit V. Dighe, Marcus Becker, Maarten J. van den Broek, Jan-Willem van Wingerden, Adam Stock, Matthew Cole, Renzo Ruisi, Ervin Bossanyi, Niklas Requate, Simon Strnad, Jonas Schmidt, Lukas Vollmer, Ishaan Sood, and Johan Meyers
Wind Energ. Sci., 7, 1791–1825, https://doi.org/10.5194/wes-7-1791-2022, https://doi.org/10.5194/wes-7-1791-2022, 2022
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The FarmConners benchmark is the first of its kind to bring a wide variety of data sets, control settings, and model complexities for the (initial) assessment of wind farm flow control benefits. Here we present the first part of the benchmark results for three blind tests with large-scale rotors and 11 participating models in total, via direct power comparisons at the turbines as well as the observed or estimated power gain at the wind farm level under wake steering control strategy.
Niels Troldborg, Søren J. Andersen, Emily L. Hodgson, and Alexander Meyer Forsting
Wind Energ. Sci., 7, 1527–1532, https://doi.org/10.5194/wes-7-1527-2022, https://doi.org/10.5194/wes-7-1527-2022, 2022
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This article shows that the power performance of a wind turbine may be very different in flat and complex terrain. This is an important finding because it shows that the power output of a given wind turbine is governed by not only the available wind at the position of the turbine but also how the ambient flow develops in the region behind the turbine.
Mads H. Aa. Madsen, Frederik Zahle, Sergio González Horcas, Thanasis K. Barlas, and Niels N. Sørensen
Wind Energ. Sci., 7, 1471–1501, https://doi.org/10.5194/wes-7-1471-2022, https://doi.org/10.5194/wes-7-1471-2022, 2022
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This work presents a shape optimization framework based on computational fluid dynamics. The design framework is used to optimize wind turbine blade tips for maximum power increase while avoiding that extra loading is incurred. The final results are shown to align well with related literature. The resulting tip shape could be mounted on already installed wind turbines as a sleeve-like solution or be conceived as part of a modular blade with tips designed for site-specific conditions.
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.
Jana Fischereit, Kurt Schaldemose Hansen, Xiaoli Guo Larsén, Maarten Paul van der Laan, Pierre-Elouan Réthoré, and Juan Pablo Murcia Leon
Wind Energ. Sci., 7, 1069–1091, https://doi.org/10.5194/wes-7-1069-2022, https://doi.org/10.5194/wes-7-1069-2022, 2022
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Wind turbines extract kinetic energy from the flow to create electricity. This induces a wake of reduced wind speed downstream of a turbine and consequently downstream of a wind farm. Different types of numerical models have been developed to calculate this effect. In this study, we compared models of different complexity, together with measurements over two wind farms. We found that higher-fidelity models perform better and the considered rapid models cannot fully capture the wake effect.
Alessandro Sebastiani, Alfredo Peña, Niels Troldborg, and Alexander Meyer Forsting
Wind Energ. Sci., 7, 875–886, https://doi.org/10.5194/wes-7-875-2022, https://doi.org/10.5194/wes-7-875-2022, 2022
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The power performance of a wind turbine is often tested with the turbine standing in a row of several wind turbines, as it is assumed that the performance is not affected by the neighbouring turbines. We test this assumption with both simulations and measurements, and we show that the power performance can be either enhanced or lowered by the neighbouring wind turbines. Consequently, we also show how power performance testing might be biased when performed on a row of several wind turbines.
Wei Fu, Alfredo Peña, and Jakob Mann
Wind Energ. Sci., 7, 831–848, https://doi.org/10.5194/wes-7-831-2022, https://doi.org/10.5194/wes-7-831-2022, 2022
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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.
Mads Baungaard, Maarten Paul van der Laan, and Mark Kelly
Wind Energ. Sci., 7, 783–800, https://doi.org/10.5194/wes-7-783-2022, https://doi.org/10.5194/wes-7-783-2022, 2022
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Wind turbine wakes are dependent on the atmospheric conditions, and it is therefore important to be able to simulate in various different atmospheric conditions. This paper concerns the specific case of an unstable atmospheric surface layer, which is the lower part of the typical daytime atmospheric boundary layer. A simple flow model is suggested and tested for a range of single-wake scenarios, and it shows promising results for velocity deficit predictions.
Marc Imberger, Xiaoli Guo Larsén, and Neil Davis
Adv. Geosci., 56, 77–87, https://doi.org/10.5194/adgeo-56-77-2021, https://doi.org/10.5194/adgeo-56-77-2021, 2021
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Events like mid-latitude storms with their high winds have an impact on wind energy production and forecasting of such events is crucial. This study investigates the capabilities of a global weather prediction model MPAS and looks at how key parameters like storm intensity, arrival time and duration are represented compared to measurements and traditional methods. It is found that storm intensity is represented well while model drifts negatively influence estimation of arrival time and duration.
Mark Kelly, Søren Juhl Andersen, and Ásta Hannesdóttir
Wind Energ. Sci., 6, 1227–1245, https://doi.org/10.5194/wes-6-1227-2021, https://doi.org/10.5194/wes-6-1227-2021, 2021
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Via 11 years of measurements, we made a representative ensemble of wind ramps in terms of acceleration, mean speed, and shear. Constrained turbulence and large-eddy simulations were coupled to an aeroelastic model for each ensemble member. Ramp acceleration was found to dominate the maxima of thrust-associated loads, with a ramp-induced increase of 45 %–50 % plus ~ 3 % per 0.1 m/s2 of bulk ramp acceleration magnitude. The LES indicates that the ramps (and such loads) persist through the farm.
Davide Conti, Nikolay Dimitrov, Alfredo Peña, and Thomas Herges
Wind Energ. Sci., 6, 1117–1142, https://doi.org/10.5194/wes-6-1117-2021, https://doi.org/10.5194/wes-6-1117-2021, 2021
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We carry out a probabilistic calibration of the Dynamic Wake Meandering (DWM) model using high-spatial- and high-temporal-resolution nacelle-based lidar measurements of the wake flow field. The experimental data were collected from the Scaled Wind Farm Technology (SWiFT) facility in Texas. The analysis includes the velocity deficit, wake-added turbulence, and wake meandering features under various inflow wind and atmospheric-stability conditions.
Davide Conti, Vasilis Pettas, Nikolay Dimitrov, and Alfredo Peña
Wind Energ. Sci., 6, 841–866, https://doi.org/10.5194/wes-6-841-2021, https://doi.org/10.5194/wes-6-841-2021, 2021
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We define two lidar-based procedures for improving the accuracy of wind turbine load assessment under wake conditions. The first approach incorporates lidar observations directly into turbulence fields serving as inputs for aeroelastic simulations; the second approach imposes lidar-fitted wake deficit time series on the turbulence fields. The uncertainty in the lidar-based power and load predictions is quantified for a variety of scanning configurations and atmosphere turbulence conditions.
Maarten Paul van der Laan, Mark Kelly, and Mads Baungaard
Wind Energ. Sci., 6, 777–790, https://doi.org/10.5194/wes-6-777-2021, https://doi.org/10.5194/wes-6-777-2021, 2021
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Wind farms operate in the atmospheric boundary layer, and their performance is strongly dependent on the atmospheric conditions. We propose a simple model of the atmospheric boundary layer that can be used as an inflow model for wind farm simulations for isolating a number of atmospheric effects – namely, the change in wind direction with height and atmospheric boundary layer depth. In addition, the simple model is shown to be consistent with two similarity theories.
Thales Fava, Mikaela Lokatt, Niels Sørensen, Frederik Zahle, Ardeshir Hanifi, and Dan Henningson
Wind Energ. Sci., 6, 715–736, https://doi.org/10.5194/wes-6-715-2021, https://doi.org/10.5194/wes-6-715-2021, 2021
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This work develops a simplified framework to predict transition to turbulence on wind-turbine blades. The model is based on the boundary-layer and parabolized stability equations, including rotation and three-dimensionality effects. We show that these effects may promote transition through highly oblique Tollmien–Schlichting (TS) or crossflow modes at low radii, and they should be considered for a correct transition prediction. At high radii, transition tends to occur through 2D TS modes.
Alfredo Peña, Branko Kosović, and Jeffrey D. Mirocha
Wind Energ. Sci., 6, 645–661, https://doi.org/10.5194/wes-6-645-2021, https://doi.org/10.5194/wes-6-645-2021, 2021
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We investigate the ability of a community-open weather model to simulate the turbulent atmosphere by comparison with measurements from a 250 m mast at a flat site in Denmark. We found that within three main atmospheric stability regimes, idealized simulations reproduce closely the characteristics of the observations with regards to the mean wind, direction, turbulent fluxes, and turbulence spectra. Our work provides foundation for the use of the weather model in multiscale real-time simulations.
Christian Grinderslev, Niels Nørmark Sørensen, Sergio González Horcas, Niels Troldborg, and Frederik Zahle
Wind Energ. Sci., 6, 627–643, https://doi.org/10.5194/wes-6-627-2021, https://doi.org/10.5194/wes-6-627-2021, 2021
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This study investigates aero-elasticity of wind turbines present in the turbulent and chaotic wind flow of the lower atmosphere, using fluid–structure interaction simulations. This method combines structural response computations with high-fidelity modeling of the turbulent wind flow, using a novel turbulence model which combines the capabilities of large-eddy simulations for atmospheric flows with improved delayed detached eddy simulations for the separated flow near the rotor.
Özge Sinem Özçakmak, Helge Aagaard Madsen, Niels Nørmark Sørensen, and Jens Nørkær Sørensen
Wind Energ. Sci., 5, 1487–1505, https://doi.org/10.5194/wes-5-1487-2020, https://doi.org/10.5194/wes-5-1487-2020, 2020
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Accurate prediction of the laminar-turbulent transition process is critical for design and prediction tools to be used in the industrial design process, particularly for the high Reynolds numbers experienced by modern wind turbines. Laminar-turbulent transition behavior of a wind turbine blade section is investigated in this study by means of field experiments and 3-D computational fluid dynamics (CFD) rotor simulations.
Pedro Santos, Alfredo Peña, and Jakob Mann
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-960, https://doi.org/10.5194/acp-2020-960, 2020
Preprint withdrawn
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We show that the vector of vertical flux of horizontal momentum and the vector of the mean vertical gradient of horizontal velocity are not aligned, based on Doppler wind lidar observations up to 500 m, both offshore and onshore. We illustrate that a mesoscale model output matches the observed mean wind speed and momentum fluxes well, but that this model output as well as idealized large-eddy simulations have deviations with the observations when looking at the turning of the wind.
Davide Conti, Nikolay Dimitrov, and Alfredo Peña
Wind Energ. Sci., 5, 1129–1154, https://doi.org/10.5194/wes-5-1129-2020, https://doi.org/10.5194/wes-5-1129-2020, 2020
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We propose a method for carrying out wind turbine load validation in wake conditions using measurements from forward-looking nacelle lidars. The uncertainty of aeroelastic load predictions is quantified against wind turbine on-board sensor data. This work demonstrates the applicability of nacelle-mounted lidar measurements to extend load and power validations under wake conditions and highlights the main challenges.
Andrey Sogachev, Dalibor Cavar, Mark Kelly, Ebba Dellwik, Tobias Klaas, and Paul Kühn
Adv. Sci. Res., 17, 53–61, https://doi.org/10.5194/asr-17-53-2020, https://doi.org/10.5194/asr-17-53-2020, 2020
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Recently an objective method was suggested to translate realistic vegetation characteristics into spatially varying values of effective roughness. This parameter allows prediction of wind flow over vegetation using models, without incorporating local drag forces in each grid volume of a three-dimensional model domain. Results of the flow simulations over different forested sites show that an approach based on a roughness representation of forest is appropriate only for the flat terrain.
Christian Grinderslev, Federico Belloni, Sergio González Horcas, and Niels Nørmark Sørensen
Wind Energ. Sci., 5, 543–560, https://doi.org/10.5194/wes-5-543-2020, https://doi.org/10.5194/wes-5-543-2020, 2020
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This study focuses on coupled computational fluid and structural dynamics simulations of a dynamic structural test of a wind turbine blade, as performed in laboratories. It is found that drag coefficients used for simulations, when planning fatigue tests, underestimate air resistance to the dynamic motion that the blade undergoes during tests. If this is not corrected for, this can result in the forces applied to the blade actually being lower in reality during tests than what was planned.
Maarten Paul van der Laan, Mark Kelly, Rogier Floors, and Alfredo Peña
Wind Energ. Sci., 5, 355–374, https://doi.org/10.5194/wes-5-355-2020, https://doi.org/10.5194/wes-5-355-2020, 2020
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The design of wind turbines and wind farms can be improved by increasing the accuracy of the inflow models representing the atmospheric boundary layer (ABL). In this work we employ numerical simulations of the idealized ABL, which can represent the mean effects of Coriolis and buoyancy forces and surface roughness. We find a new model-based similarity that provides a better understanding of the idealized ABL. In addition, we extend the model to include effects of convective buoyancy forces.
Alexander R. Meyer Forsting, Georg R. Pirrung, and Néstor Ramos-García
Wind Energ. Sci., 5, 349–353, https://doi.org/10.5194/wes-5-349-2020, https://doi.org/10.5194/wes-5-349-2020, 2020
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Simulations of wind farms allow the estimation of the forces acting on the turbines and thus their lifetime and power production. Representing the actual geometric shape of turbines in a realistic atmospheric flow is computationally expensive; therefore they are modelled in a simplified manner. Unfortunately, these simplifications negatively impact the estimated forces. We developed an open-source aerodynamic model that corrects the forces, giving more accurate estimates of lifetime and power.
Maarten Paul van der Laan, Søren Juhl Andersen, and Pierre-Elouan Réthoré
Wind Energ. Sci., 4, 645–651, https://doi.org/10.5194/wes-4-645-2019, https://doi.org/10.5194/wes-4-645-2019, 2019
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Wind farm layouts are designed by simple engineering wake models, which are fast to compute but also include a high uncertainty. Higher-fidelity models, such as Reynolds-averaged Navier–Stokes, can be used to verify optimized wind farm layouts, although the computational costs are high due to the large number of cases that are needed to calculate the annual energy production. This article presents a new wind turbine control method to speed up the high-fidelity simulations by a factor of 2–3.
Ásta Hannesdóttir and Mark Kelly
Wind Energ. Sci., 4, 385–396, https://doi.org/10.5194/wes-4-385-2019, https://doi.org/10.5194/wes-4-385-2019, 2019
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The wind turbine safety standard includes a coherent gust model with a wind speed increase and direction change of 10 s. With the increasing rotor size of modern wind turbines this model is criticized for being uniform across these large rotors. In this study we investigate measurements of coherent gusts with a ramp-like increase in wind speed. We define a new method for ramp detection and characterization and compare it with the coherent gust model from the wind turbine safety standard.
Alexander R. Meyer Forsting, Georg Raimund Pirrung, and Néstor Ramos-García
Wind Energ. Sci., 4, 369–383, https://doi.org/10.5194/wes-4-369-2019, https://doi.org/10.5194/wes-4-369-2019, 2019
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The actuator line was intended as a lifting line technique for CFD applications. In this paper we prove – theoretically and practically – that smearing the forces of the actuator line in the flow domain leads to smeared velocity fields. By combining a near-wake representation of the trailed vorticity with a viscous vortex core model, the missing induction from the smeared velocity is recovered and a lifting line for CFD simulations established.
Ásta Hannesdóttir, Mark Kelly, and Nikolay Dimitrov
Wind Energ. Sci., 4, 325–342, https://doi.org/10.5194/wes-4-325-2019, https://doi.org/10.5194/wes-4-325-2019, 2019
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We investigate large wind speed fluctuations from a 10-year period at the Danish coastal site Høvsøre. The most extreme fluctuations are not turbulent but due to larger-scale weather phenomena. We find how these fluctuations impact wind turbines using simulations. The results are then compared to an extreme turbulence model described in the wind turbine safety standards, and it is found that the loads on the different turbine components are not the same as what the standard describes.
Maarten Paul van der Laan, Søren Juhl Andersen, Néstor Ramos García, Nikolas Angelou, Georg Raimund Pirrung, Søren Ott, Mikael Sjöholm, Kim Hylling Sørensen, Julio Xavier Vianna Neto, Mark Kelly, Torben Krogh Mikkelsen, and Gunner Christian Larsen
Wind Energ. Sci., 4, 251–271, https://doi.org/10.5194/wes-4-251-2019, https://doi.org/10.5194/wes-4-251-2019, 2019
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Over the past few decades, single-rotor wind turbines have increased in size with the blades being extended toward lengths of 100 m. An alternative upscaling of turbines can be achieved by using multi-rotor wind turbines. In this article, measurements and numerical simulations of a utility-scale four-rotor wind turbine show that rotor interaction leads to increased energy production and faster wake recovery; these findings may allow for the design of wind farms with improved energy production.
Jianting Du, Rodolfo Bolaños, Xiaoli Guo Larsén, and Mark Kelly
Ocean Sci., 15, 361–377, https://doi.org/10.5194/os-15-361-2019, https://doi.org/10.5194/os-15-361-2019, 2019
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Ocean surface waves generated by wind and dissipated by white capping are two important physics processes for numerical wave simulations. In this study, a new pair of wind–wave generation and dissipation source functions is implemented in the wave model SWAN, and it shows better performance in real wave simulations during two North Sea storms. The new source functions can be further used in other wave models for both academic and engineering purposes.
Mads H. Aa. Madsen, Frederik Zahle, Niels N. Sørensen, and Joaquim R. R. A. Martins
Wind Energ. Sci., 4, 163–192, https://doi.org/10.5194/wes-4-163-2019, https://doi.org/10.5194/wes-4-163-2019, 2019
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The wind energy industry relies heavily on CFD to analyze new designs. This paper investigates a way to utilize CFD further upstream the design process where lower-fidelity methods are used. We present the first comprehensive 3-D CFD adjoint-based shape optimization of a 10 MW modern offshore wind turbine. The present work shows that, with the right tools, we can model the entire geometry, including the root, and optimize modern wind turbine rotors at the cost of a few hundred CFD evaluations.
Alfredo Peña, Ebba Dellwik, and Jakob Mann
Atmos. Meas. Tech., 12, 237–252, https://doi.org/10.5194/amt-12-237-2019, https://doi.org/10.5194/amt-12-237-2019, 2019
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We propose a method to assess the accuracy of turbulence measurements by sonic anemometers. The idea is to compute the ratio of the vertical to along-wind velocity spectrum within the inertial subrange. We found that the Metek USA-1 and the Campbell CSAT3 sonic anemometers do not show the expected theoretical ratio. A wind-tunnel-based correction recovers the expected ratio for the USA-1. A correction for the CSAT3 does not, illustrating that this sonic anemometer suffers from flow distortion.
Nikolay Dimitrov, Mark C. Kelly, Andrea Vignaroli, and Jacob Berg
Wind Energ. Sci., 3, 767–790, https://doi.org/10.5194/wes-3-767-2018, https://doi.org/10.5194/wes-3-767-2018, 2018
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Wind energy site suitability assessment procedures often require estimating the loads a wind turbine will be subject to when installed. The estimation is often time-consuming and requires several iterations. We have developed a procedure for quick and accurate estimation of site-specific wind turbine loads. Our approach employs computationally efficient parametric models that are calibrated to high-fidelity load simulations. The result is a significant reduction in computation efforts.
Georg Raimund Pirrung and Maarten Paul van der Laan
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2018-59, https://doi.org/10.5194/wes-2018-59, 2018
Revised manuscript not accepted
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Wind turbine loading decreases towards the blade tip due to the velocities induced by the tip vortex and the spanwise flow. It has been shown that the tip loss factor applied on the aerodynamic forces should be different for the axial and tangential loading of the turbine due to the rotation of the resulting force vector caused by the induced velocity. The present article contains the derivation of a simple correction for the tangential load factor that takes this rotation into account.
Mark Kelly
Wind Energ. Sci., 3, 533–543, https://doi.org/10.5194/wes-3-533-2018, https://doi.org/10.5194/wes-3-533-2018, 2018
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This paper shows how a definitive part of the commonly used Mann (1994) atmospheric turbulence model (its so-called eddy lifetime) implies that the model parameters can be directly related to typical measurements in wind energy projects. Most importantly, the characteristic turbulence length scale is found in terms of commonly measured (10 min mean) quantities (shear and standard deviation of wind speed); this estimator is found to give useful results, over different sites and flow regimes.
Laura Valldecabres, Alfredo Peña, Michael Courtney, Lueder von Bremen, and Martin Kühn
Wind Energ. Sci., 3, 313–327, https://doi.org/10.5194/wes-3-313-2018, https://doi.org/10.5194/wes-3-313-2018, 2018
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This paper focuses on the use of scanning lidars for very short-term forecasting of wind speeds in a near-coastal area. An extensive data set of offshore lidar measurements up to 6 km has been used for this purpose. Using dual-doppler measurements, the topographic characteristics of the area have been modelled. Assuming Taylor's frozen turbulence and applying the topographic corrections, we demonstrate that we can forecast wind speeds with more accuracy than the benchmarks persistence or ARIMA.
Jakob Mann, Alfredo Peña, Niels Troldborg, and Søren J. Andersen
Wind Energ. Sci., 3, 293–300, https://doi.org/10.5194/wes-3-293-2018, https://doi.org/10.5194/wes-3-293-2018, 2018
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Turbulence is usually assumed to be unmodified by the stagnation occurring in front of a wind turbine rotor. All manufacturers assume this in their dynamic load calculations. If this assumption is not true it might bias the load calculations and the turbines might not be designed optimally. We investigate the assumption with a Doppler lidar measuring forward from the top of the nacelle and find small but systematic changes in the approaching turbulence that depend on the power curve.
Alfredo Peña, Kurt Schaldemose Hansen, Søren Ott, and Maarten Paul van der Laan
Wind Energ. Sci., 3, 191–202, https://doi.org/10.5194/wes-3-191-2018, https://doi.org/10.5194/wes-3-191-2018, 2018
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We analyze the wake of the Anholt offshore wind farm in Denmark by intercomparing models and measurements. We also look at the effect of the land on the wind farm by intercomparing mesoscale winds and measurements. Annual energy production and capacity factor estimates are performed using different approaches. Lastly, the uncertainty of the wake models is determined by bootstrapping the data; we find that the wake models generally underestimate the wake losses.
Maarten Paul van der Laan and Niels Nørmark Sørensen
Wind Energ. Sci., 2, 285–294, https://doi.org/10.5194/wes-2-285-2017, https://doi.org/10.5194/wes-2-285-2017, 2017
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In recent years, wind farms have grown in size and are more frequently placed in wind farm clusters. This means that large-scale effects such as the interaction of the Coriolis force and wind farm wakes are becoming more important for designing energy efficient wind farms. The literature disagrees on the turning direction of a wind farm wake due to the Coriolis force. In this article, we explain why the Coriolis force turns a wind farm wake clockwise in the Northern Hemisphere.
Mark Kelly and Hans E. Jørgensen
Wind Energ. Sci., 2, 189–209, https://doi.org/10.5194/wes-2-189-2017, https://doi.org/10.5194/wes-2-189-2017, 2017
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Here we give a basic form for uncertainty in mean wind speed predicted at one site via measurements taken at another site due to uncertainty in surface roughness when using industry-standard European Wind Atlas (e.g., WAsP) method. We also provide an approximate power-curve form and method to further estimate uncertainty in turbine energy production; this is also useful in AEP estimates. Some implications are also discussed, e.g., prediction over forest or with mesoscale model output.
Alfredo Peña, Jakob Mann, and Nikolay Dimitrov
Wind Energ. Sci., 2, 133–152, https://doi.org/10.5194/wes-2-133-2017, https://doi.org/10.5194/wes-2-133-2017, 2017
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Nacelle lidars are nowadays extensively used to scan the turbine inflow. Thus, it is important to characterize turbulence from their measurements. We present two methods to perform turbulence estimation and demonstrate them using two types of lidars. With one method we can estimate the along-wind unfiltered variance accurately. With the other we can estimate the filtered radial velocity variance accurately and velocity-tensor parameters under neutral and high wind-speed conditions.
Alfredo Peña, Andreas Bechmann, Davide Conti, and Nikolas Angelou
Wind Energ. Sci., 1, 101–114, https://doi.org/10.5194/wes-1-101-2016, https://doi.org/10.5194/wes-1-101-2016, 2016
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We have developed flow models from different complexities. Unfortunately, high quality and reliable wind observations affected by obstacles are rare and so we have few means to evaluate our models. We have therefore performed a campaign in which we measured the effect of a fence on the atmosphere using laser-based instruments. The effect can still be noticed as far as 11 fence heights. A wake theory seems to predict the obstacle effect when we are looking at distances beyond 6 fence heights.
Dalibor Cavar, Pierre-Elouan Réthoré, Andreas Bechmann, Niels N. Sørensen, Benjamin Martinez, Frederik Zahle, Jacob Berg, and Mark C. Kelly
Wind Energ. Sci., 1, 55–70, https://doi.org/10.5194/wes-1-55-2016, https://doi.org/10.5194/wes-1-55-2016, 2016
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Feasibility of a freely available CFD tool, OpenFOAM, in calculating flows of general relevance to the wind industry is investigated by comparing several aspects of its performance to a well-established in-house EllipSys3D solver. The comparison is focused on CFD solver demands regarding grid generation process and computational time.
The quality and accuracy of the achieved results are investigated by conducting the computations using identical/similar solver parameters and numerical setups..
Related subject area
Thematic area: Fluid mechanics | Topic: Wakes and wind farm aerodynamics
Hyperparameter tuning framework for calibrating analytical wake models using SCADA data of an offshore wind farm
Synchronised WindScanner field measurements of the induction zone between two closely spaced wind turbines
Wind farm structural response and wake dynamics for an evolving stable boundary layer: computational and experimental comparisons
A Numerical Investigation of Multirotor Systems with Vortex-Generating Modes for Regenerative Wind Energy: Validation Against Experimental Data
Improvements to the dynamic wake meandering model by incorporating the turbulent Schmidt number
An actuator sector model for wind power applications: a parametric study
Wind tunnel investigations of an individual pitch control strategy for wind farm power optimization
The near-wake development of a wind turbine operating in stalled conditions – Part 1: Assessment of numerical models
Data-driven optimisation of wind farm layout and wake steering with large-eddy simulations
Floating wind turbine motion signature in the far-wake spectral content – a wind tunnel experiment
Breakdown of the velocity and turbulence in the wake of a wind turbine – Part 1: Large-eddy-simulation study
Breakdown of the velocity and turbulence in the wake of a wind turbine – Part 2: Analytical modelling
Free-vortex models for wind turbine wakes under yaw misalignment – a validation study on far-wake effects
A method to correct for the effect of blockage and wakes on power performance measurements
Vortex model of the aerodynamic wake of airborne wind energy systems
Investigating energy production and wake losses of multi-gigawatt offshore wind farms with atmospheric large-eddy simulation
The wind farm as a sensor: learning and explaining orographic and plant-induced flow heterogeneities from operational data
Multi-point in situ measurements of turbulent flow in a wind turbine wake and inflow with a fleet of uncrewed aerial systems
Addressing deep array effects and impacts to wake steering with the cumulative-curl wake model
Actuator line model using simplified force calculation methods
Brief communication: A clarification of wake recovery mechanisms
Predictive and stochastic reduced-order modeling of wind turbine wake dynamics
Wind turbine wake simulation with explicit algebraic Reynolds stress modeling
Including realistic upper atmospheres in a wind-farm gravity-wave model
Diederik van Binsbergen, Pieter-Jan Daems, Timothy Verstraeten, Amir R. Nejad, and Jan Helsen
Wind Energ. Sci., 9, 1507–1526, https://doi.org/10.5194/wes-9-1507-2024, https://doi.org/10.5194/wes-9-1507-2024, 2024
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Wind farm yield assessment often relies on analytical wake models. Calibrating these models can be challenging due to the stochastic nature of wind. We developed a calibration framework that performs a multi-phase optimization on the tuning parameters using time series SCADA data. This yields a parameter distribution that more accurately reflects reality than a single value. Results revealed notable variation in resultant parameter values, influenced by nearby wind farms and coastal effects.
Anantha Padmanabhan Kidambi Sekar, Paul Hulsman, Marijn Floris van Dooren, and Martin Kühn
Wind Energ. Sci., 9, 1483–1505, https://doi.org/10.5194/wes-9-1483-2024, https://doi.org/10.5194/wes-9-1483-2024, 2024
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We present induction zone measurements conducted with two synchronised lidars at a two-turbine wind farm. The induction zone flow was characterised for free, fully waked and partially waked flows. Due to the short turbine spacing, the lidars captured the interaction of the atmospheric boundary layer, induction zone and wake, evidenced by induction asymmetry and induction zone–wake interactions. The measurements will aid the process of further improving existing inflow and wake models.
Kelsey Shaler, Eliot Quon, Hristo Ivanov, and Jason Jonkman
Wind Energ. Sci., 9, 1451–1463, https://doi.org/10.5194/wes-9-1451-2024, https://doi.org/10.5194/wes-9-1451-2024, 2024
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This paper presents a three-way verification and validation between an engineering-fidelity model, a high-fidelity model, and measured data for the wind farm structural response and wake dynamics during an evolving stable boundary layer of a small wind farm, generally with good agreement.
Flavio Avila Correia Martins, Alexander van Zuijlen, and Carlos Simao Ferreira
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2024-72, https://doi.org/10.5194/wes-2024-72, 2024
Revised manuscript accepted for WES
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This paper explores an innovative way to boost wind farm efficiency by integrating atmospheric boundary layer control devices with multirotor systems. These devices speed up the recovery of wind power in wind farm flows. Using both simulations and laboratory experiments, this study shows that the proposed technology can significantly improve power output per land area of wind farms and allow for tighter turbine spacing, potentially leading to more space-efficient and cost-effective wind farms.
Peter Brugger, Corey D. Markfort, and Fernando Porté-Agel
Wind Energ. Sci., 9, 1363–1379, https://doi.org/10.5194/wes-9-1363-2024, https://doi.org/10.5194/wes-9-1363-2024, 2024
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The dynamic wake meandering model (DWMM) assumes that wind turbine wakes are transported like a passive tracer by the large-scale turbulence of the atmospheric boundary layer. We show that both the downstream transport and the lateral transport of the wake have differences from the passive tracer assumption. We then propose to include the turbulent Schmidt number into the DWMM to account for the less efficient transport of momentum and show that it improves the quality of the model predictions.
Mohammad Mehdi Mohammadi, Hugo Olivares-Espinosa, Gonzalo Pablo Navarro Diaz, and Stefan Ivanell
Wind Energ. Sci., 9, 1305–1321, https://doi.org/10.5194/wes-9-1305-2024, https://doi.org/10.5194/wes-9-1305-2024, 2024
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This paper has put forward a set of recommendations regarding the actuator sector model implementation details to improve the capability of the model to reproduce similar results compared to those obtained by an actuator line model, which is one of the most common ways used for numerical simulations of wind farms, while providing significant computational savings. This includes among others the velocity sampling method and a correction of the sampled velocities to calculate the blade forces.
Franz V. Mühle, Florian M. Heckmeier, Filippo Campagnolo, and Christian Breitsamter
Wind Energ. Sci., 9, 1251–1271, https://doi.org/10.5194/wes-9-1251-2024, https://doi.org/10.5194/wes-9-1251-2024, 2024
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Wind turbines influence each other, and these wake effects limit the power production of downstream turbines. Controlling turbines collectively and not individually can limit such effects. We experimentally investigate a control strategy increasing mixing in the wake. We want to see the potential of this so-called Helix control for power optimization and understand the flow physics. Our study shows that the control technique leads to clearly faster wake recovery and thus higher power production.
Pascal Weihing, Marion Cormier, Thorsten Lutz, and Ewald Krämer
Wind Energ. Sci., 9, 933–962, https://doi.org/10.5194/wes-9-933-2024, https://doi.org/10.5194/wes-9-933-2024, 2024
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This study evaluates different approaches to simulate the near-wake flow of a wind turbine. The test case is in off-design conditions of the wind turbine, where the flow is separated from the blades and therefore very difficult to predict. The evaluation of simulation techniques is key to understand their limitations and to deepen the understanding of the near-wake physics. This knowledge can help to derive new wind farm design methods for yield-optimized farm layouts.
Nikolaos Bempedelis, Filippo Gori, Andrew Wynn, Sylvain Laizet, and Luca Magri
Wind Energ. Sci., 9, 869–882, https://doi.org/10.5194/wes-9-869-2024, https://doi.org/10.5194/wes-9-869-2024, 2024
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This paper proposes a computational method to maximise the power production of wind farms through two strategies: layout optimisation and yaw angle optimisation. The proposed method relies on high-fidelity computational modelling of wind farm flows and is shown to be able to effectively maximise wind farm power production. Performance improvements relative to conventional optimisation strategies based on low-fidelity models can be attained, particularly in scenarios of increased flow complexity.
Benyamin Schliffke, Boris Conan, and Sandrine Aubrun
Wind Energ. Sci., 9, 519–532, https://doi.org/10.5194/wes-9-519-2024, https://doi.org/10.5194/wes-9-519-2024, 2024
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This paper studies the consequences of floater motions for the wake properties of a floating wind turbine. Since wake interactions are responsible for power production loss in wind farms, it is important that we know whether the tools that are used to predict this production loss need to be upgraded to take into account these aspects. Our wind tunnel study shows that the signature of harmonic floating motions can be observed in the far wake of a wind turbine, when motions have strong amplitudes.
Erwan Jézéquel, Frédéric Blondel, and Valéry Masson
Wind Energ. Sci., 9, 97–117, https://doi.org/10.5194/wes-9-97-2024, https://doi.org/10.5194/wes-9-97-2024, 2024
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Wind turbine wakes affect the production and lifecycle of downstream turbines. They can be predicted with the dynamic wake meandering (DWM) method. In this paper, the authors break down the velocity and turbulence in the wake of a wind turbine into several terms. They show that it is implicitly assumed in the DWM that some of these terms are neglected. With high-fidelity simulations, it is shown that this can lead to some errors, in particular for the maximum turbulence added by the wake.
Erwan Jézéquel, Frédéric Blondel, and Valéry Masson
Wind Energ. Sci., 9, 119–139, https://doi.org/10.5194/wes-9-119-2024, https://doi.org/10.5194/wes-9-119-2024, 2024
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Analytical models allow us to quickly compute the decreased power output and lifetime induced by wakes in a wind farm. This is achieved by evaluating the modified velocity and turbulence in the wake. In this work, we present a new model based on the velocity and turbulence breakdowns presented in Part 1. This new model is physically based, allows us to compute the whole turbulence profile (rather than the maximum value) and is built to take atmospheric stability into account.
Maarten J. van den Broek, Delphine De Tavernier, Paul Hulsman, Daan van der Hoek, Benjamin Sanderse, and Jan-Willem van Wingerden
Wind Energ. Sci., 8, 1909–1925, https://doi.org/10.5194/wes-8-1909-2023, https://doi.org/10.5194/wes-8-1909-2023, 2023
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As wind turbines produce power, they leave behind wakes of slow-moving air. We analyse three different models to predict the effects of these wakes on downstream wind turbines. The models are validated with experimental data from wind tunnel studies for steady and time-varying conditions. We demonstrate that the models are suitable for optimally controlling wind turbines to improve power production in large wind farms.
Alessandro Sebastiani, James Bleeg, and Alfredo Peña
Wind Energ. Sci., 8, 1795–1808, https://doi.org/10.5194/wes-8-1795-2023, https://doi.org/10.5194/wes-8-1795-2023, 2023
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The power curve of a wind turbine indicates the turbine power output in relation to the wind speed. Therefore, power curves are critically important to estimate the production of future wind farms as well as to assess whether operating wind farms are functioning correctly. Since power curves are often measured in wind farms, they might be affected by the interactions between the turbines. We show that these effects are not negligible and present a method to correct for them.
Filippo Trevisi, Carlo E. D. Riboldi, and Alessandro Croce
Wind Energ. Sci., 8, 999–1016, https://doi.org/10.5194/wes-8-999-2023, https://doi.org/10.5194/wes-8-999-2023, 2023
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Modeling the aerodynamic wake of airborne wind energy systems (AWESs) is crucial to properly estimating power production and to designing such systems. The velocities induced at the AWES from its own wake are studied with a model for the near wake and one for the far wake, using vortex methods. The model is validated with the lifting-line free-vortex wake method implemented in QBlade.
Peter Baas, Remco Verzijlbergh, Pim van Dorp, and Harm Jonker
Wind Energ. Sci., 8, 787–805, https://doi.org/10.5194/wes-8-787-2023, https://doi.org/10.5194/wes-8-787-2023, 2023
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This work studies the energy production and wake losses of large offshore wind farms with a large-eddy simulation model. Therefore, 1 year of actual weather has been simulated for a suite of hypothetical 4 GW wind farm scenarios. The results suggest that production numbers increase significantly when the rated power of the individual turbines is larger while keeping the total installed capacity the same. Also, a clear impact of atmospheric stability on the energy production is found.
Robert Braunbehrens, Andreas Vad, and Carlo L. Bottasso
Wind Energ. Sci., 8, 691–723, https://doi.org/10.5194/wes-8-691-2023, https://doi.org/10.5194/wes-8-691-2023, 2023
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The paper presents a new method in which wind turbines in a wind farm act as local sensors, in this way detecting the flow that develops within the power plant. Through this technique, we are able to identify effects on the flow generated by the plant itself and by the orography of the terrain. The new method not only delivers a flow model of much improved quality but can also help in understanding phenomena that drive the farm performance.
Tamino Wetz and Norman Wildmann
Wind Energ. Sci., 8, 515–534, https://doi.org/10.5194/wes-8-515-2023, https://doi.org/10.5194/wes-8-515-2023, 2023
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In the present study, for the first time, the SWUF-3D fleet of multirotors is deployed for field measurements on an operating 2 MW wind turbine (WT) in complex terrain. The fleet of multirotors has the potential to fill the meteorological gap of observations in the near wake of WTs with high-temporal and high-spatial-resolution wind vector measurements plus temperature, humidity and pressure. The flow up- and downstream of the WT is measured simultaneously at multiple spatial positions.
Christopher J. Bay, Paul Fleming, Bart Doekemeijer, Jennifer King, Matt Churchfield, and Rafael Mudafort
Wind Energ. Sci., 8, 401–419, https://doi.org/10.5194/wes-8-401-2023, https://doi.org/10.5194/wes-8-401-2023, 2023
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This paper introduces the cumulative-curl wake model that allows for the fast and accurate prediction of wind farm energy production wake interactions. The cumulative-curl model expands several existing wake models to make the simulation of farms more accurate and is implemented in a computationally efficient manner such that it can be used for wind farm layout design and controller development. The model is validated against high-fidelity simulations and data from physical wind farms.
Gonzalo Pablo Navarro Diaz, Alejandro Daniel Otero, Henrik Asmuth, Jens Nørkær Sørensen, and Stefan Ivanell
Wind Energ. Sci., 8, 363–382, https://doi.org/10.5194/wes-8-363-2023, https://doi.org/10.5194/wes-8-363-2023, 2023
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In this paper, the capacity to simulate transient wind turbine wake interaction problems using limited wind turbine data has been extended. The key novelty is the creation of two new variants of the actuator line technique in which the rotor blade forces are computed locally using generic load data. The analysis covers a partial wake interaction case between two wind turbines for a uniform laminar inflow and for a turbulent neutral atmospheric boundary layer inflow.
Maarten Paul van der Laan, Mads Baungaard, and Mark Kelly
Wind Energ. Sci., 8, 247–254, https://doi.org/10.5194/wes-8-247-2023, https://doi.org/10.5194/wes-8-247-2023, 2023
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Understanding wind turbine wake recovery is important to mitigate energy losses in wind farms. Wake recovery is often assumed or explained to be dependent on the first-order derivative of velocity. In this work we show that wind turbine wakes recover mainly due to the second-order derivative of the velocity, which transport momentum from the freestream towards the wake center. The wake recovery mechanisms and results of a high-fidelity numerical simulation are illustrated using a simple model.
Søren Juhl Andersen and Juan Pablo Murcia Leon
Wind Energ. Sci., 7, 2117–2133, https://doi.org/10.5194/wes-7-2117-2022, https://doi.org/10.5194/wes-7-2117-2022, 2022
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Simulating the turbulent flow inside large wind farms is inherently complex and computationally expensive. A new and fast model is developed based on data from high-fidelity simulations. The model captures the flow dynamics with correct statistics for a wide range of flow conditions. The model framework provides physical insights and presents a generalization of high-fidelity simulation results beyond the case-specific scenarios, which has significant potential for future turbulence modeling.
Mads Baungaard, Stefan Wallin, Maarten Paul van der Laan, and Mark Kelly
Wind Energ. Sci., 7, 1975–2002, https://doi.org/10.5194/wes-7-1975-2022, https://doi.org/10.5194/wes-7-1975-2022, 2022
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Wind turbine wakes in the neutral atmospheric surface layer are simulated with Reynolds-averaged Navier–Stokes (RANS) using an explicit algebraic Reynolds stress model. Contrary to standard two-equation turbulence models, it can predict turbulence anisotropy and complex physical phenomena like secondary motions. For the cases considered, it improves Reynolds stress, turbulence intensity, and velocity deficit predictions, although a more top-hat-shaped profile is observed for the latter.
Koen Devesse, Luca Lanzilao, Sebastiaan Jamaer, Nicole van Lipzig, and Johan Meyers
Wind Energ. Sci., 7, 1367–1382, https://doi.org/10.5194/wes-7-1367-2022, https://doi.org/10.5194/wes-7-1367-2022, 2022
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Recent research suggests that offshore wind farms might form such a large obstacle to the wind that it already decelerates before reaching the first turbines. Part of this phenomenon could be explained by gravity waves. Research on these gravity waves triggered by mountains and hills has found that variations in the atmospheric state with altitude can have a large effect on how they behave. This paper is the first to take the impact of those vertical variations into account for wind farms.
Cited articles
Allaerts, D. and Meyers, J.: Gravity Waves and Wind-Farm Efficiency in Neutral and Stable Conditions, Bound.-Lay. Meteorol., 166, 269–299,
https://doi.org/10.1007/s10546-017-0307-5, 2018. a
Antonini, E. G., Romero, D. A., and Amon, C. H.: Improving CFD wind farm
simulations incorporating wind direction uncertainty, Renew. Energy, 133,
1011–1023, https://doi.org/10.1016/j.renene.2018.10.084, 2019. a
Bak, C., Zahle, F., Bitsche, R., Kim, T., Yde, A., Henriksen, L. C., Natarajan, A., and Hansen, M. H.: Description of the DTU 10 MW Reference Wind Turbine, Tech. Rep. I-0092, Technical University of Denmark, https://orbit.dtu.dk/files/55645274/The_DTU_10MW_Reference_Turbine_Christian_Bak.pdf (last access: 23 May 2023), 2013. a, b
Boussinesq, M. J.: Théorie de l'écoulement tourbillonnant et tumultueux des liquides, Gauthier-Villars et fils, Paris, France, 1897. a
Churchfield, M. J., Schreck, S. J., Martinez, L. A., Meneveau, C., and Spalart, P. R.: An Advanced Actuator Line Method for Wind Energy Applications and Beyond, in: 35th Wind Energy Symposium, 9–13 January 2017,
Grapevine, Texas, https://doi.org/10.2514/6.2017-1998, 2017. a
COWI: Vindressource, layouts og energiproduktion for Bornholm I + II,
Nordsøen II + III og området vest for nordsøen II + III, Tech. Rep. A132994-2-3, COWI A/S, Lyngby, Denmark,
https://ens.dk/sites/ens.dk/files/Vindenergi/2-3_vindressource_layouts_og_energiproduktion.pdf (last access: 23 May 2023), 2020. a
Danielson, J. J. and Gesch, D. B.: Global multi-resolution terrain elevation
data 2010 (GMTED2010), USGS, https://doi.org/10.3133/ofr20111073, 2011. a
Dellwik, E., van der Laan, M., Angelou, N., Mann, J., and Sogachev, A.:
Observed and modeled near-wake flow behind a solitary tree, Agr. Forest Meteorol., 265, 78–87, https://doi.org/10.1016/j.agrformet.2018.10.015, 2019. a, b, c, d
Donlon, C. J., Martin, M., Stark, J., Roberts-Jones, J., Fiedler, E., and
Wimmer, W.: The Operational Sea Surface Temperature and Sea Ice Analysis
(OSTIA) system, Remote Sens. Environ., 116, 140–158,
https://doi.org/10.1016/j.rse.2010.10.017, 2012. a
Dörenkämper, M., Olsen, B. T., Witha, B., Hahmann, A. N., Davis, N. N., Barcons, J., Ezber, Y., García-Bustamante, E., González-Rouco, J. F., Navarro, J., Sastre-Marugán, M., Sīle, T., Trei, W., Žagar, M.,
Badger, J., Gottschall, J., Sanz Rodrigo, J., and Mann, J.: The Making of the
New European Wind Atlas – Part 2: Production and evaluation, Geosci. Model Dev., 13, 5079–5102, https://doi.org/10.5194/gmd-13-5079-2020, 2020. a
DTU Wind Energy: PyWakeEllipSys v3.2,
https://topfarm.pages.windenergy.dtu.dk/cuttingedge/pywake/pywake_ellipsys/ (last access: 23 May 2023), 2022b. a
Durran, D. and Klemp, J.: A compressible model for the simulation of moist
mountain waves, Am. Meteorol. Soc., 111, 2341–2361, 1983. a
Esau, I. N.: Parameterization of a surface drag coefficient in conventionally
neutral planetary boundary layer, Ann. Geophys., 22, 3353–3362,
https://doi.org/10.5194/angeo-22-3353-2004, 2004. a
Fischereit, J., Schaldemose Hansen, K., Larsén, X. G., van der Laan, M. P., Réthoré, P.-E., and Murcia Leon, J. P.: Comparing and validating
intra-farm and farm-to-farm wakes across different mesoscale and
high-resolution wake models, Wind Energ. Sci., 7, 1069–1091,
https://doi.org/10.5194/wes-7-1069-2022, 2022. a
Fitch, A. C., Olson, J. B., Lundquist, J. K., Dudhia, J., Gupta, A. K.,
Michalakes, J., and Barstad, I.: Local and Mesoscale Impacts of Wind Farms as Parameterized in a Mesoscale NWP Model, Mon. Weather Rev., 140, 3017–3038, https://doi.org/10.1175/MWR-D-11-00352.1, 2012. a, b, c, d
Forsting, A. M. and Troldborg, N.: Generalised grid requirements minimizing the actuator line angle-of-attack error, J. Phys.: Conf. Ser., 1618, 052001, https://doi.org/10.1088/1742-6596/1618/5/052001, 2020. a
4coffshore.com: Global offshore wind farm database,
https://map.4coffshore.com/offshorewind/ (last access: 23 August 2022), 2022. a
Frandsen, S.: Turbulence and turbulence-generated structural loading in wind
turbine clusters, PhD thesis, risø-R-1188(EN), https://orbit.dtu.dk/files/12674798/ris_r_1188.pdf (last access: 23 May 2023), 2007. a
Gaumond, M., Réthoré, P.-E., Ott, S., Peña, A., Bechmann, A., and Hansen,
K. S.: Evaluation of the wind direction uncertainty and its impact on wake
modeling at the Horns Rev offshore wind farm, Wind Energy, 17, 1169–1178,
https://doi.org/10.1002/we.1625, 2014. a
Göçmen, T., van der Laan, M. P., Réthoré, P. E., Peña Diaz, A., Larsen, G. C., and Ott, S.: Wind turbine wake models developed at the technical university of Denmark: A review, Renew. Sustain. Energ. Rev., 60, 752–769, 2016. a
Grell, G. A. and Freitas, S. R.: A scale and aerosol aware stochastic
convective parameterization for weather and air quality modeling, Atmos.
Chem. Phys., 14, 5233–5250, https://doi.org/10.5194/acp-14-5233-2014, 2014. a
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A.,
Muñoz‐Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D.,
Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P.,
Biavati, G., Bidlot, J., Bonavita, M., Chiara, G., Dahlgren, P., Dee, D.,
Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R. J., Hólm, E., Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J.: The ERA5 global reanalysis, Q. J. Roy. Meteorol. Soc., 146, 1999–2049, https://doi.org/10.1002/qj.3803, 2020. a
Hong, S.-Y., Dudhia, J., and Chen, S.-H.: A Revised Approach to Ice
Microphysical Processes for the Bulk Parameterization of Clouds and
Precipitation, Mon. Weather Rev., 132, 103–120,
https://doi.org/10.1175/1520-0493(2004)132<0103:aratim>2.0.co;2, 2004. a
Iacono, M. J., Delamere, J. S., Mlawer, E. J., Shephard, M. W., Clough, S. A., and Collins, W. D.: Radiative forcing by long-lived greenhouse gases:
Calculations with the AER radiative transfer models, J. Geophys. Res., 113, D13103, https://doi.org/10.1029/2008jd009944, 2008. a
Jonkman, J., Butterfield, S., Musial, W., and Scott, G.: Definition of a 5-MW Reference Wind Turbine for Offshore System Development, Tech. rep., National Renewable Energy Laboratory, https://www.nrel.gov/docs/fy09osti/38060.pdf (last access: 23 May 2023), 2009. a
Kelly, M., Cersosimo, R. A., and Berg, J.: A universal wind profile for the
inversion-capped neutral atmospheric boundary layer, Q. J. Roy. Meteorol. Soc., 145, 982–992, https://doi.org/10.1002/qj.3472, 2019. a, b
Kosović, B., Munoz, P. J., Juliano, T. W., Martilli, A., Eghdami, M.,
Barros, A. P., and Haupt, S. E.: Three-Dimensional Planetary Boundary Layer
Parameterization for High-Resolution Mesoscale Simulations, J. Phys.: Conf.
Ser., 1452, 012080, https://doi.org/10.1088/1742-6596/1452/1/012080, 2020. a
Launder, B. and Spalding, D.: The numerical computation of turbulent flows,
Comput. Meth. Appl. Mech. Eng., 3, 269–289,
https://doi.org/10.1016/0045-7825(74)90029-2, 1974. a
Liu, L., Gadde, S. N., and Stevens, R. J. A. M.: Universal Wind Profile for
Conventionally Neutral Atmospheric Boundary Layers, Phys. Rev. Lett., 126,
104502, https://doi.org/10.1103/PhysRevLett.126.104502, 2021. a, b
Michelsen, J. A.: Basis3D - a platform for development of multiblock PDE
solvers, Tech. Rep. AFM 92-05, Technical University of Denmark, Lyngby,
Denmark, https://orbit.dtu.dk/files/272917945/Michelsen_J_Basis3D.pdf (last access: 23 May 2023), 1992. a
Mikkelsen, R.: Actuator Disc Methods Applied to Wind Turbines, PhD thesis,
Technical University of Denmark, https://orbit.dtu.dk/files/5452244/Robert.PDF (last access: 23 May 2023), 2003. a
Nakanishi, M. and Niino, H.: An improved Mellor-Yamada Level-3 model: Its
numerical stability and application to a regional prediction of advection
fog, Bound.-Lay. Meteorol., 119, 397–407, https://doi.org/10.1007/s10546-005-9030-8, 2006. a
Ott, S. and Nielsen, M.: Developments of the offshore wind turbine wake model Fuga, Tech. Rep. I-0046, Technical University of Denmark, https://orbit.dtu.dk/files/118472784/DTU_Wind_Energy_E_0046.pdf (last access: 23 May 2023), 2014. a
Pedersen, J. G., Svensson, E., Poulsen, L., and Nygaard, N. G.: Turbulence
Optimized Park model with Gaussian wake profile, J. Phys. Conf. Ser., 2265, 022063, https://doi.org/10.1088/1742-6596/2265/2/022063, 2022. a, b, c
Peña, A., Mirocha, J. D., and van der Laan, M. P.: Evaluation of the Fitch wind-farm wake parametrization with large-eddy simulations of wakes using the Weather Research and Forecasing model, Mon. Weather Rev., 150,
3051–3064, 2022. a
Poulter, B., MacBean, N., Hartley, A., Khlystova, I., Arino, O., Betts, R.,
Bontemps, S., Boettcher, M., Brockmann, C., Defourny, P., Hagemann, S.,
Herold, M., Kirches, G., Lamarche, C., Lederer, D., Ottlé, C., Peters, M., and Peylin, P.: Plant functional type classification for earth system models: results from the European Space Agency's Land Cover Climate Change Initiative, Geosci. Model Dev., 8, 2315–2328, https://doi.org/10.5194/gmd-8-2315-2015, 2015. a
Réthoré, P.-E.: Wind Turbine Wake in Atmospheric Turbulence, PhD thesis, Aalborg University, Risø DTU, Roskilde, Denmark, https://orbit.dtu.dk/files/4548747/ris-phd-53.pdf (last access: 23 May 2023), 2009. a
Réthoré, P.-E., van der Laan, M. P., Troldborg, N., Zahle, F., and
Sørensen, N. N.: Verification and validation of an actuator disc model,
Wind Energy, 17, 919–937, https://doi.org/10.1002/we.1607, 2014. a, b, c
Rybchuk, A., Juliano, T. W., Lundquist, J. K., Rosencrans, D., Bodini, N., and Optis, M.: The sensitivity of the Fitch wind farm parameterization to a three-dimensional planetary boundary layer scheme, Wind Energ. Sci., 7, 2085–2098, https://doi.org/10.5194/wes-7-2085-2022, 2022. a
Skamarock, W. C., Klemp, J. B., Dudhia, J., Gill, D. O., Liu, Z., Berner, J.,
Wang, W., Powers, J. G., Duda, M. G., Barker, D. M., and Huang, X.-Y.: A
Description of the Advanced Research WRF Version 4, Tech. rep., NCAR Tech. Note NCAR/TN-556+STR, NCAR, https://doi.org/10.5065/1dfh-6p97, 2019. a
Sogachev, A., Kelly, M., and Leclerc, M. Y.: Consistent Two-Equation Closure
Modelling for Atmospheric Research: Buoyancy and Vegetation Implementations,
Bound.-Lay. Meteorol., 145, 307–327, https://doi.org/10.1007/s10546-012-9726-5, 2012. a, b, c
Sørensen, J. N. and Larsen, G. C.: A Minimalistic Prediction Model to
Determine Energy Production and Costs of Offshore Wind Farms, Energies, 14,
2, https://doi.org/10.3390/en14020448, 2021. a
Sørensen, J. N. and Shen, W. Z.: Numerical Modeling of Wind Turbine Wakes, J. Fluids Eng., 124, 393–399, https://doi.org/10.1115/1.1471361, 2002. a
Sørensen, J. N., Nilsson, K., Ivanell, S., Asmuth, H., and Mikkelsen, R. F.: Analytical body forces in numerical actuator disc model of wind turbines, Renew. Energy, 147, 2259, https://doi.org/10.1016/j.renene.2019.09.134, 2020. a, b
Sørensen, N. N.: General purpose flow solver applied to flow over hills,
PhD thesis, Risø National Laboratory, Roskilde, Denmark, https://orbit.dtu.dk/files/12280331/Ris_R_827.pdf (last access: 23 May 2023), 1994. a
Sørensen, N. N., Bechmann, A., Johansen, J., Myllerup, L., Botha, P.,
Vinther, S., and Nielsen, B. S.: Identification of severe wind conditions
using a Reynolds Averaged Navier–Stokes solver, J. Phys.: Conf. Ser., 75, 1–13, https://doi.org/10.1088/1742-6596/75/1/012053, 2007. a
Spalart, P. and Rumsey, C.: Effective inflow conditions for turbulence models
in aerodynamic calculations, AIAA J., 45, 2544–2553, 2007. a
Storey, R. C., Norris, S. E., and Cater, J. E.: An actuator sector method for
efficient transient wind turbine simulation, Wind Energy, 18, 699–711,
https://doi.org/10.1002/we.1722, 2015. a
Technical University of Denmark: Sophia HPC Cluster, https://doi.org/10.57940/FAFC-6M81, 2019. a
Tewari, M., Chen, F., Wang, W., Dudhi, J., LeMone, M., Mitchell, K., Ek, M.,
Gayno, G., Wegiel, J., and Cuenca, R. H.: Implementation and verification of
the unified Noah land surface model in the WRF model, in: 20th Conference on
Weather Analysis and Forecasting/16th Conference on Numerical Weather
Prediction, Seattle, WA, USA, http://n2t.net/ark:/85065/d7fb523p (last access: 23 May 2023), 2004. a
Troldborg, N.: Actuator Line Modeling of Wind Turbine Wakes, PhD thesis, DTU, https://orbit.dtu.dk/files/5289075/niels_troldborg.pdf (last access: 23 May 2023), 2008. a
Troldborg, N. and Meyer Forsting, A. R.: A simple model of the wind turbine
induction zone derived from numerical simulations, Wind Energy, 20, 2011–2020,
https://doi.org/10.1002/we.2137, 2017. a
van der Laan, M. P. and Sørensen, N. N.: A 1D version of EllipSys, Tech.
Rep. DTU Wind Energy E-0141, Technical University of Denmark, https://orbit.dtu.dk/files/130854208/DTU_Wind_Energy_E_0141.pdf (last access: 23 May 2023), 2017a. a
van der Laan, M. P. and Sørensen, N. N.: Why the Coriolis force turns a wind farm wake clockwise in the Northern Hemisphere, Wind Energy Science, 2,
285–294, https://doi.org/10.5194/wes-2-285-2017, 2017b. a, b, c, d
van der Laan, M. P., Sørensen, N. N., Réthoré, P.-E., Mann, J.,
Kelly, M., and Troldborg, N.: The k–ε–fP model applied to double wind turbine wakes using different actuator disk force methods, Wind Energy, 18, 2223–2240, https://doi.org/10.1002/we.1816, 2015a.
a, b, c
van der Laan, M. P., Sørensen, N. N., Réthoré, P.-E., Mann, J.,
Kelly, M., Troldborg, N., Hansen, K. S., and Murcia, J. P.: The
k–ε–fP model applied to wind farms, Wind Energy, 18, 2065–2084, https://doi.org/10.1002/we.1804, 2015b. a, b
van der Laan, M. P., Sørensen, N. N., Réthoré, P.-E., Mann, J.,
Kelly, M., Troldborg, N., Schepers, J. G., and Machefaux, E.: An improved
k–ε model applied to a wind turbine wake in atmospheric
turbulence, Wind Energy, 18, 889–907, https://doi.org/10.1002/we.1736, 2015c. a, b, c
van der Laan, M. P., Andersen, S. J., and Réthoré, P.-E.: Brief
communication: Wind-speed-independent actuator disk control for faster annual
energy production calculations of wind farms using computational fluid
dynamics, Wind Energ. Sci., 4, 645–651, https://doi.org/10.5194/wes-4-645-2019, 2019. a
van der Laan, M. P., Andersen, S. J., Réthoré, P.-E., Baungaard, M., Sørensen, J. N., and Troldborg, N.: Faster wind farm AEP calculations with CFD using a generalized wind turbine model, J. Phys.: Conf. Ser., 2265, 022030, https://doi.org/10.1088/1742-6596/2265/2/022030, 2022. a, b
Wu, Y.-T. and Porté-Agel, F.: Large-Eddy Simulation of Wind-Turbine Wakes: Evaluation of Turbine Parametrisations, Bound.-Lay. Meteorol., 138,
345–366, https://doi.org/10.1007/s10546-010-9569-x, 2011. a
Short summary
Offshore wind farms are more commonly installed in wind farm clusters, where wind farm interaction can lead to energy losses. In this work, an efficient numerical method is presented that can be used to estimate these energy losses. The novel method is verified with higher-fidelity numerical models and validated with measurements of an existing wind farm cluster.
Offshore wind farms are more commonly installed in wind farm clusters, where wind farm...
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