The noise generated by megawatt-level wind turbine blades has a significant impact on the surrounding envi-ronment.When the blades are operating at full speed,trailing edge separation vortices are easily formed,and the kinematic performances of these vortices have an important influence on the sound pressure characteristics.To study the impact mecha-nism of trailing edge indentations on the sound pressure characteristics of blades,the NACA4415 airfoil is chosen as the re-search object,and the k-ε SST turbulence model is used to calculate the acoustic parameters in the coupled region of three different surface structures of airfoils at full operating speeds.The results show that the indented airfoil can significantly re-duce the distribution range and probability of high-frequency trailing edge separation vortices compared to the smooth air-foil.Indenting the upper surface of the airfoil can greatly reduce the helicity of the trailing edge separation vortices and the distribution range of the vortex core,meanwhile ensure that the aerodynamic characteristic curve of the airfoil is within the 90%confidence interval of the smooth airfoil.The maximum sound pressure reduction rate for the indented airfoil is 1.46%,and the maximum sound power reduction rate is 31.50%.This conclusion lays a theoretical foundation for future re-search on environmental friendly blade design.
维普
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