VALIDATION OF A WIND TURBINE NOISE PROPAGATION MODEL AGAINST FIELD MEASUREMENTS

Predicting the noise radiated by a wind farm needs to take into account many parameters such as wind turbine operational conditions, wind and temperature profiles, atmospheric turbulence, ground impedance and topography. In this study, we aim at validating a wind turbine noise prediction model that combines Amiet's theory to calculate trailing edge noise and turbulence interaction noise with a wide-angle parabolic equation valid in moving media to account for long range acoustic propagation effects. The model considers the wind turbine as an extended and rotating noise source. The model predictions are compared to field measurements recorded during ten days around an eight-turbine single row wind farm. As the terrain is flat and the roughness is relatively homogeneous, the meteorological lidar and a mast data are supposed to be range-independent. Using representative values for the ground parameters, the model gives the correct interference patterns in the third octave band spectrum. Accurate predictions of the third octave band spectra averaged over 10 minutes are obtained for propagation distances up to 1300 meters, although the influence of background noise becomes more significant as the distance increases.