Turbulent kinetic energy estimates from profiling wind lidar and provisional derivation to calculate C2n
Military operations on target practice and wind farms demand on knowledge of the turbulent state and wind speed in the surrounding atmosphere. However, the definition of turbulence is completely different in both cases. In the military context we speak about optical turbulence in the wind industry, kinetic turbulence is essential. In the following we want to present an approach that combines both turbulences. In the vicinity of a military test range and 120 m high wind turbines a new Doppler LIDAR system (WINDCUBETM v200s, Leosphere, France) was operated to investigate the vertical distribution of turbulent kinetic energy and the spatial distribution of the radial wind speed in the atmospheric boundary layer. Deployments in different modes were carried out to get best estimations of turbulence. Vertical profile measurements obtained with two ultrasonic anemometers at discrete levels on an 80 m high mast close to the position of the LIDAR were used for comparison. We present an adapted algorithm to calculate the TKE from a low-frequency signal (vertical profile every 10 s) and a approach to calculate C2n. The first preliminary results show a good agreement. Results on diurnal cycles of the TKE in different stability regimes and local effects will be discussed.
Eijk, Alexander M.J. van