Flow in the wake of wind turbines : turbulance spectral analysis by wind tunnel test

Abstract

The interaction between the incident wind and wind turbines in a wind farm causes mean velocity deficit and increased levels of turbulence in the wake. The turbulent flow is characterized by the superposition of wind turbine wakes. In this work, the technique of turbulence spectral evaluation for reduced scale models in a boundary layer wind tunnel is presented, and different measurements of velocity fluctuations are analysed. The results allow evaluating the spectrum for different frequency ranges and the differences of the spectral behaviour between the incident wind and the turbine wake flow.