1114 Study on aerofoil noise with inflow turbulence by using the active turbulence generator

Abstract

Recently, it's a problem of aerodynamic noise radiated from wind turbine. One of numerical aeroacoustical code for wind turbine noise prediction is FAST, constructed based on the airfoil noise prediction model. However, prediction accuracy in codes isn't enough. In this study, it's aimed for database construction of airfoil noise on the inflow turbulence and for improvement of the prediction model based on the results by wind tunnel test using active turbulence generator (ATG). In this paper, it's shown that airfoil noise can be measured under the turbulence intensity of 10 to 20 % and eddy scale of 300 to 1600 mm. The three types of airfoil models have wing sections of NACA0012, DU96 and S831, their chord length of 150 mm and aspect ratio of 3.3 as two-dimensional model, respectively. It's clear that turbulent flow affects as same frequency range on velocity spectra as on sound spectra, but airfoil shapes do not affect it.