Numerical Prediction of the Aerodynamics and Aeroacoustics of a Horizontal Axis Wind Turbine

Abstract. This study used low-frequency-based numerical methods to predict noise radiating from rotating horizontal axis wind turbine (HAWT) blades. ANSYS FLUENT was used to calculate flow parameters in the vicinity of blade surfaces, as required for the Ffowcs Williams–Hawkings (FW–H) equation. The numerical model was validated against the experimental results from the National Renewable Energy Laboratory Phase VI wind turbine blades. The coupling analysis was integrated with four Reynolds-averaged Navier–Stokes turbulence models and the FW–H equation under different boundary conditions. The SST k-ω and V2f turbulence models produced results in agreement with the available experimental pressure-coefficient and relative-velocity-distribution data. An INER 25-kW HAWT was employed to predict noise frequency distribution at nine points from the tower on the windward and leeward sides under different operating conditions. Noise frequency distributions on the windward and leeward sides showed little differences, whereas those on the left and right sides with respect to the tower were different owing to wind-shear influence. The peak amplitude of the noise was inversely proportional to the increasing distance from the tower but proportional to the wind and rotation speeds.