Sogachev, AndreyAndreySogachevCavar, DaliborDaliborCavarKelly, MarkMarkKellyDellwik, EbbaEbbaDellwikKlaas, TobiasTobiasKlaasKühn, PaulPaulKühn2022-03-062022-03-062020https://publica.fraunhofer.de/handle/publica/26553310.5194/asr-17-53-2020Parameterizing the effect of vertically-distributed vegetation through an effective roughness (z0,eff) - whereby momentum loss through a three-dimensional foliage volume is represented as momentum loss over an area at one vertical level - can facilitate the use of forest data in flow models, to any level of detail, and simultaneously reduce computational cost. Results of numerical experiments and comparison with observations show that a modelling approach based on z0,eff can estimate wind speed and turbulence levels over forested areas, at heights of interest for wind energy applications (∼60 m and higher), but only above flat terrain. Caution must be exercised in the application of such a model to zones of forest edges. Advanced flow models capable of incorporating local (distributed) drag forces are recommended for complex terrain covered by forest.enwind energyflow modellingRANSforestsjournal article