Wind Tunnel Measurements of the Aerodynamic Noise of Blade Sections

摘要

In 1991, research project sponsored by the Netherlands Agency for Energy andEnvironment was initiated to map all possibilities to reduce the flow-induced noise of wind turbines. It was found that (1) in full-scale experiments, it is not possible to discriminate between the different noise generating mechanisms. However, to develop efficient measures for the reduction of wind-turbine noise, an accurate prediction of all the noise generating mechanism is necessary, (2) trailing-edge noise can possibly be reduced significantly by the application of serrated trailing edges, and (3) the experimental validation of the present models describing the noise caused by the turbulence in the atmospheric boundary layer is limited. In a wind tunnel, the noise generating mechanisms can be studied separately by using a correlation technique. Hence, it is possible to make a detailed comparison of the prediction formulae for these mechanisms, and to study the influence of certain details of the blade geometry.