Turbulence statistics from three different nacelle lidars

Abstract. Atmospheric turbulence can be characterized by the Reynolds stress tensor, which consists of second-order moments wind field components. Most commercial nacelle lidars cannot estimate all components tensor due to their limited number beams; most along-wind velocity variance relatively well. Other are however also important understand behavior of, e.g., vertical profile and meandering wakes. The SpinnerLidar, a research lidar with multiple beams very high sampling frequency, was deployed together two in forward-looking mode on Vestas V52 turbine scan inflow. Here, we compare lidar-derived estimates those from sonic anemometer using both numerical simulations measurements nearby mast. We show that these lidars, SpinnerLidar is only one able retrieve For two- four-beam study different methods compute variance. By SpinnerLidar's Doppler spectra radial velocity, partly compensate for lidar's probe volume averaging effect thus reduce systematic error estimates. find variances velocities estimated maximum spectrum less affected compared median or centroid spectrum.