Impact of Forest Density on Atmospheric Boundary-Layer Flow and Turbulence for Wind Energy Applications
摘要
Nowadays, it is common to build wind farms in forested areas as wind-energy production is growing rapidly. However, surrounding forests change the local wind conditions drastically, and therefore, there is a need to understand the interaction between local wind conditions and forest properties. The present work aims to investigate the impact of various forest densities on the flow characteristics in the lower part of the Atmospheric Boundary-Layer (ABL). Here, Large-Eddy Simulations (LES) of wind flow over horizontally homogeneous forest canopies were carried out for four different forest densities. The selected forest cases range from extremely dense forests with a Leaf Area Index (LAI) of 10.5 to extremely sparse forests with an LAI of 0.44. The LES results reveal a strong impact of forest density on wind shear and turbulence at rotor-relevant heights. At hub height, the wind-shear exponent varies by up to 16% across the four forest densities, while turbulent kinetic energy (TKE) shows a non-monotonic dependence on LAI. Intermediate forests (LAI