Broadband Noise Prediction of Small Horizontal Wind Turbine Rotor

초록

As small wind turbines are located much close to the residents, the emission level of such wind turbines becomes one of the major social issues. This paper presents the results of numerical prediction of small wind turbine rotor noise by using a Computational Fluid Dynamics (CFD) code and an in-house code for aero-acoustic calculation based on Ffowcs Williams-Hawking’s (FW-H) equations. The wind turbine model has a three-bladed rotor of 1.5 m diameter. The flow-field around wind turbine rotor model was simulated by solving three-dimensional, unsteady, finite-volume formulated Reynolds-averaged Navier-Stokes equation with shear stress transport turbulence model, whereas far-field aero-acoustic analysis was performed by solving FW-H equations. The capabilities of in-house FW-H equation based code were validated acoustic signatures from vehicle engine cooling fan, which were measured by reverberant room method. The noise characteristics of three sets of blades with different twist and chord length distributions at a series of cross sections have been simulated and discussed.