Sensitivity analysis of influential parameters for wind turbinenoise
Résumé
Wind turbine noise is directly concerned by physical phenomena related to long-range sound propagation, i.e. ground effects (roughness, impedance), and micrometeorological effects (mean refraction, intermittency fluctuations, small-scale turbulence scattering). In order to estimate the relative influence of these environmental and influent parameters on acoustic propagation, we present a sensitivity analysis based on a propagation model and on a specific numerical experiment design produced by a Morris screening method. The model used is a Parabolic Equation model (MW-WAPE) which takes into account ground effects (absorption through acoustic impedance & diffusion through surface roughness) and micrometeorological effects (mean refraction through the vertical gradient of effective celerity & atmospheric turbulence through the random Fourier modes technique). The results allow the quantification of the global variability and uncertainties associated with main phenomena occurring in the emission-propagation-reception process. The results will allow quantifying the overall variability and uncertainties associated with the emission-propagation-reception sound chain. A better knowledge of these uncertainties will provide a better control of the quality of wind turbines noise prediction in an inhomogeneous outdoor environment.