Investigation of Doppler Features From Wind Turbine Scattering

We examine the Doppler features from wind turbine scattering through a series of model measurements. Both backscattered and forward-scattered data are collected in the laboratory at Ku-band from various wind turbine models undergoing rotation. The tested models include a 1:160 scale model turbine, a three-arm wire model, and a small wind turbine from Bergey Windpower with 2' blades. The findings from the wire turbine model are corroborated by simulations performed using the Numerical Electromagnetics Code (NEC). Detailed accounts of the physics behind the observed Doppler features due to multiple scattering, near-field effects, and blade-shape effects are reported.