12 Jun 2020
| 12 Jun 2020
Numerical modelling of the wind over forests: roughness versus canopy drag
Wind Energy Department, Technical University of Denmark, Roskilde,
Denmark
Dalibor Cavar
Wind Energy Department, Technical University of Denmark, Roskilde,
Denmark
Mark Kelly
Wind Energy Department, Technical University of Denmark, Roskilde,
Denmark
Ebba Dellwik
Wind Energy Department, Technical University of Denmark, Roskilde,
Denmark
Tobias Klaas
Fraunhofer IEE, Königstor 59, 34119 Kassel, Germany
Paul Kühn
Fraunhofer IEE, Königstor 59, 34119 Kassel, Germany
Related authors
L. Zhou, R. Gierens, A. Sogachev, D. Mogensen, J. Ortega, J. N. Smith, P. C. Harley, A. J. Prenni, E. J. T. Levin, A. Turnipseed, A. Rusanen, S. Smolander, A. B. Guenther, M. Kulmala, T. Karl, and M. Boy
Atmos. Chem. Phys., 15, 8643–8656, https://doi.org/10.5194/acp-15-8643-2015, https://doi.org/10.5194/acp-15-8643-2015, 2015
D. Mogensen, R. Gierens, J. N. Crowley, P. Keronen, S. Smolander, A. Sogachev, A. C. Nölscher, L. Zhou, M. Kulmala, M. J. Tang, J. Williams, and M. Boy
Atmos. Chem. Phys., 15, 3909–3932, https://doi.org/10.5194/acp-15-3909-2015, https://doi.org/10.5194/acp-15-3909-2015, 2015
B. Bonn, E. Bourtsoukidis, T. S. Sun, H. Bingemer, L. Rondo, U. Javed, J. Li, R. Axinte, X. Li, T. Brauers, H. Sonderfeld, R. Koppmann, A. Sogachev, S. Jacobi, and D. V. Spracklen
Atmos. Chem. Phys., 14, 10823–10843, https://doi.org/10.5194/acp-14-10823-2014, https://doi.org/10.5194/acp-14-10823-2014, 2014
Maarten Paul van der Laan, Mark Kelly, Mads Baungaard, and Antariksh Dicholkar
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2024-23, https://doi.org/10.5194/wes-2024-23, 2024
Preprint under review for WES
Short summary
Short summary
Wind turbines are increasing in size and operate more frequently above the atmospheric surface layer, which requires improved inflow models for numerical simulations of turbine interaction. In this work, a novel steady-state model of the atmospheric boundary layer (ABL) is introduced. Numerical wind turbine flow simulations subjected to shallow and tall ABLs are performed and the results show a good agreement with results from two high-fidelity numerical simulation codes.
Mark Kelly and Maarten Paul van der Laan
Wind Energ. Sci., 8, 975–998, https://doi.org/10.5194/wes-8-975-2023, https://doi.org/10.5194/wes-8-975-2023, 2023
Short summary
Short summary
The turning of the wind with height, which is known as veer, can affect wind turbine performance. Thus far meteorology has only given idealized descriptions of veer, which has not yet been related in a way readily usable for wind energy. Here we derive equations for veer in terms of meteorological quantities and provide practically usable forms in terms of measurable shear (change in wind speed with height). Flow simulations and measurements at turbine heights support these developments.
Maarten Paul van der Laan, Oscar García-Santiago, Mark Kelly, Alexander Meyer Forsting, Camille Dubreuil-Boisclair, Knut Sponheim Seim, Marc Imberger, Alfredo Peña, Niels Nørmark Sørensen, and Pierre-Elouan Réthoré
Wind Energ. Sci., 8, 819–848, https://doi.org/10.5194/wes-8-819-2023, https://doi.org/10.5194/wes-8-819-2023, 2023
Short summary
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.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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.
Tobias Klaas-Witt and Stefan Emeis
Wind Energ. Sci., 7, 413–431, https://doi.org/10.5194/wes-7-413-2022, https://doi.org/10.5194/wes-7-413-2022, 2022
Short summary
Short summary
Light detection and ranging (lidar) has become a valuable technology to assess the wind resource at hub height of modern wind turbines. However, because of their measurement principle, common lidars suffer from errors at orographically complex, i.e. hilly or mountainous, sites. This study analyses the impact of the five main influencing factors in a non-dimensional, model-based parameter study.
Nikolas Angelou, Jakob Mann, and Ebba Dellwik
Atmos. Chem. Phys., 22, 2255–2268, https://doi.org/10.5194/acp-22-2255-2022, https://doi.org/10.5194/acp-22-2255-2022, 2022
Short summary
Short summary
In this study we use state-of-the-art scanning wind lidars to investigate the wind field in the near-wake region of a mature, open-grown tree. Our measurements provide for the first time a picture of the mean and the turbulent spatial fluctuations in the flow in the wake of a tree in its natural environment. Our observations support the hypothesis that even simple models can realistically simulate the turbulent fluctuations in the wake and thus predict the effect of trees in flow models.
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
Short summary
Short summary
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.
Toby D. Jackson, Sarab Sethi, Ebba Dellwik, Nikolas Angelou, Amanda Bunce, Tim van Emmerik, Marine Duperat, Jean-Claude Ruel, Axel Wellpott, Skip Van Bloem, Alexis Achim, Brian Kane, Dominick M. Ciruzzi, Steven P. Loheide II, Ken James, Daniel Burcham, John Moore, Dirk Schindler, Sven Kolbe, Kilian Wiegmann, Mark Rudnicki, Victor J. Lieffers, John Selker, Andrew V. Gougherty, Tim Newson, Andrew Koeser, Jason Miesbauer, Roger Samelson, Jim Wagner, Anthony R. Ambrose, Andreas Detter, Steffen Rust, David Coomes, and Barry Gardiner
Biogeosciences, 18, 4059–4072, https://doi.org/10.5194/bg-18-4059-2021, https://doi.org/10.5194/bg-18-4059-2021, 2021
Short summary
Short summary
We have all seen trees swaying in the wind, but did you know that this motion can teach us about ecology? We summarized tree motion data from many different studies and looked for similarities between trees. We found that the motion of trees in conifer forests is quite similar to each other, whereas open-grown trees and broadleaf forests show more variation. It has been suggested that additional damping or amplification of tree motion occurs at high wind speeds, but we found no evidence of this.
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
Short summary
Short summary
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.
Johan Arnqvist, Julia Freier, and Ebba Dellwik
Biogeosciences, 17, 5939–5952, https://doi.org/10.5194/bg-17-5939-2020, https://doi.org/10.5194/bg-17-5939-2020, 2020
Short summary
Short summary
Data generated by airborne laser scans enable the characterization of surface vegetation for any application that might need it, such as forest management, modeling for numerical weather prediction, or wind energy estimation. In this work we present a new algorithm for calculating the vegetation density using data from airborne laser scans. The new routine is more robust than earlier methods, and an implementation in popular programming languages accompanies the article to support new users.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
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
Short summary
Short summary
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.
Stefan Ivanell, Johan Arnqvist, Matias Avila, Dalibor Cavar, Roberto Aurelio Chavez-Arroyo, Hugo Olivares-Espinosa, Carlos Peralta, Jamal Adib, and Björn Witha
Wind Energ. Sci., 3, 929–946, https://doi.org/10.5194/wes-3-929-2018, https://doi.org/10.5194/wes-3-929-2018, 2018
Short summary
Short summary
This article describes a study in which modellers were challenged to compute the wind at a forested site with moderately complex topography. The target was to match the measured wind profile at one exact location for three directions. The input to the models consisted of detailed information on forest densities and ground height. Overall, the article gives an overview of how well different types of models are able to capture the flow physics at a moderately complex forested site.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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.
Rogier Floors, Peter Enevoldsen, Neil Davis, Johan Arnqvist, and Ebba Dellwik
Wind Energ. Sci., 3, 353–370, https://doi.org/10.5194/wes-3-353-2018, https://doi.org/10.5194/wes-3-353-2018, 2018
Short summary
Short summary
Applying erroneous boundary conditions (surface roughness) for wind flow modelling can have a large impact on the estimated performance of wind turbines, particularly in forested areas. Traditionally the estimation of the surface roughness is based on a subjective process that requires assigning a value to each land use class in the vicinity of the wind farm. Here we propose a new method which converts lidar scans from a plane into maps that can be used for wind flow modelling.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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..
C. F. Abari, A. T. Pedersen, E. Dellwik, and J. Mann
Atmos. Meas. Tech., 8, 4145–4153, https://doi.org/10.5194/amt-8-4145-2015, https://doi.org/10.5194/amt-8-4145-2015, 2015
Short summary
Short summary
Continuous-wave coherent Doppler lidars (CW CDL) are a class of short-range wind lidars. This paper presents the measurement results from a field campaign where the performance of a recently built all-fiber image-reject homodyne CW CDL is compared against a sonic anemometer. The results are weighed against another instrument, i.e., a CW CDL benefiting from a heterodyne receiver. The results show that the new system has a superior measurement performance, especially for close-to-zero velocities.
L. Zhou, R. Gierens, A. Sogachev, D. Mogensen, J. Ortega, J. N. Smith, P. C. Harley, A. J. Prenni, E. J. T. Levin, A. Turnipseed, A. Rusanen, S. Smolander, A. B. Guenther, M. Kulmala, T. Karl, and M. Boy
Atmos. Chem. Phys., 15, 8643–8656, https://doi.org/10.5194/acp-15-8643-2015, https://doi.org/10.5194/acp-15-8643-2015, 2015
D. Mogensen, R. Gierens, J. N. Crowley, P. Keronen, S. Smolander, A. Sogachev, A. C. Nölscher, L. Zhou, M. Kulmala, M. J. Tang, J. Williams, and M. Boy
Atmos. Chem. Phys., 15, 3909–3932, https://doi.org/10.5194/acp-15-3909-2015, https://doi.org/10.5194/acp-15-3909-2015, 2015
B. Bonn, E. Bourtsoukidis, T. S. Sun, H. Bingemer, L. Rondo, U. Javed, J. Li, R. Axinte, X. Li, T. Brauers, H. Sonderfeld, R. Koppmann, A. Sogachev, S. Jacobi, and D. V. Spracklen
Atmos. Chem. Phys., 14, 10823–10843, https://doi.org/10.5194/acp-14-10823-2014, https://doi.org/10.5194/acp-14-10823-2014, 2014
Cited articles
Bingöl, F.: Complex Terrain and Wind Lidars. Roskilde, Risø National
Laboratory for Sustainable Energy, Risø-PhD, No. 52(EN), 60 pp., 2010.
Blackadar, A. K. and Tennekes, H.: Asymptotic similarity in neutral
barotropic planetary boundary layers, J. Atmos. Sci., 25, 1015–20,
https://doi.org/10.1175/1520-0469(1968)025<1015:ASINBP>2.0.CO;2,
1968.
Boudreault, L.-E.: Reynolds-averaged Navier-Stokes and Large-Eddy Simulation
over and inside inhomogeneous forests, DTU Wind Energy, PhD-0042 (EN), 118 pp., 2015.
Boudreault, L.-É., Bechmann, A., Tarvainen, L., Klemedtsson, L.,
Shendryk, I., and Dellwik, E.: A LiDAR method of canopy structure retrieval
for wind modeling of heterogeneous forests, Agr. Forest Meteorol., 201,
86–97, https://doi.org/10.1016/j.agrformet.2014.10.014, 2015.
Clarke, R. H. and Hess, G. D.: Geostrophic departure and the functions A
and B of Rossby-number similarity theory, Bound.-Lay. Meteorol., 7,
261–287, https://doi.org/10.1007/BF00240832, 1974.
Dellwik, E., Bingöl, F., and Mann, J.: Flow distortion at a dense forest
edge, Q. J. Roy. Meteor. Soc., 140, 676–686, https://doi.org/10.1002/qj.2155, 2014.
Finnigan, J. J.: Turbulence in plant canopies, Annu. Rev. Fluid. Mech., 32,
519–571, https://doi.org/10.1146/annurev.fluid.32.1.519, 2000.
Freier, J.: Approaches to characterise forest structures for wind resource
assessment using airborne laser scan data, Master thesis, Department of
Mechanical Engineering, Kassel University, Kassel, 111 pp., 2017.
HVBG, Hessisches Landesamt für Bodenmanagement und Geoinformation:
Landesweites Laserscanning Hessen – Die Basis für ein Solarkataster,
with assistance of Dorn, C. and Köhler, G., Hessian
Administration Office of Land Management and Geological Information,
Wiesbaden (DE), 2010.
Koblitz, T.: CFD modelling of non-neutral atmospheric boundary layer
conditions, DTU Wind Energy PhD-0019 (EN), 104 pp., 2013.
Lefsky, M. A., Cohen, W. B., Acker, S., Parker, G. G., Spies, T. A., and
Harding, D.: Lidar remote sensing of the canopy structure and biophysical
properties of Douglas-fir western hemlock forests, Remote Sens. Environ.,
70, 339–361, https://doi.org/10.1191/0309133303pp360ra, 1999.
Mann, J., Angelou, N., Arnqvist, J., Callies, D., Cantero, E., Arroyo, R.
C., Courtney, M., Cuxart, J., Dellwik, E., Gottschall, J., Ivanell, S.,
Kuhn, P., Lea, G., Matos, C. J. S., Palma, J. M. L. M., Pauscher, L.,
Peña, A., Rodrigo, J. S., Söderberg, S., Vasiljevic, N., and
Rodrigues, C. V.: Complex terrain experiments in the New European Wind
Atlas, Philos. T. R. Soc. A, 375, https://doi.org/10.1098/rsta.2016.0101, 2017.
Melgarejo, J. W. and Deardorff, J. W.: Stability functions for the boundary
layer resistance laws based upon observed boundary layer height, J. Atmos.
Sci., 31, 1324–1333, https://doi.org/10.1175/1520-0469(1974)031<1324:SFFTBL>2.0.CO;2, 1974.
Michelsen, J. A.: Basis3d – a platform for development of multiblock pde
solvers, Technical report AFM92-05, Technical University of Denmark, 1992.
Peña, A.: Østerild: A natural laboratory for atmospheric turbulence,
J. Renewable Sustainable Energy, 11, 063302, https://doi.org/10.1063/1.5121486, 2019.
Pope, S. B.: Turbulent flows, Cambridge University Press, UK,
771 pp., 2000.
Raupach, M. R. and Shaw, R. H.: Averaging procedures for flow within
vegetation canopies, Bound.-Lay. Meteorol., 22, 79–90,
https://doi.org/10.1007/BF00128057, 1982.
Richardson, J. J., Moskal, L. M., and Kim, S. H.: Modeling approaches to
estimate effective leaf area index from aerial discrete-return LIDAR, Agr.
Forest Meterol., 149, 1152–1160, https://doi.org/10.1016/j.agrformet.2009.02.007, 2009.
Sogachev, A., Menzhulin, G. V., Heimann M., and Lloyd, J.: A simple
three-dimensional canopy – planetary boundary layer simulation model for
scalar concentrations and fluxes, Tellus B, 54, 784–819,
https://doi.org/10.3402/tellusb.v54i5.16729, 2002.
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.
Sogachev, A., Cavar, D., Bechmann, A., and Jørgensen, H. E.: Assessment
of consistent two-equation closure for forest flows, Paper presented at EWEA
Annual Conference and Exhibition, Paris, France, 2015.
Sogachev, A., Cavar, D., Kelly, M., and Bechmann, A.: Effective roughness
and displacement height over forested areas, via reduced-dimension CFD, Report of DTU Wind Energy – E, vol. 0161, 36 pp., 2017.
Sørensen, N. N.: Technical report, Risø-R-827(EN), Risø National
Laboratory, 154 pp., 2003.
Sørensen, N. N., Bechmann, A., Boudreault, L-E., Koblitz, T., Sogachev,
A., and Laan, M.: CFD for Atmospheric Flows and Wind Engineering, Lecture
Series 2016-2017, von Karman Institute for Fluid Dynamics, Belgium,
https://doi.org/10.35294/ls201701, 2017.
Troen, I. and Petersen, E. L.: European Wind Atlas. Roskilde: Risø
National Laboratory, Denmark, 656 pp., 1989.
Short summary
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.
Recently an objective method was suggested to translate realistic vegetation characteristics...
