An experiment study of the serrated trailing edge noise

Trailing edge noise, which is generated by the interaction of turbulence boundary layer and trailing edge, is the dominant component of airfoil self-noise. In last decade, many contributions have been made to the development of the theory, numerical simulation and experiment of the trailing edge noise. However, much effort is still required to advance understanding of the noise generation mechanism and for the suppression strategies. In this paper, some experimental research has been done on suppressing the airfoil noise by serrated trailing edge. The experiments are all carried out in the low-speed open jet wind tunnel, which is in the anechoic chamber. The study is focused on the influence of the angle of attack of the airfoil on the far field noise and the airfoil surface pressure. The far-field measurement shows that the serrated trailing edge is an alternative way to reduce the airfoil noise, especially for the low frequency component. Moreover, it is revealed that the noise reduction is related to the number and the shape of sawtooth. Meanwhile, the surface measurement shows a little change of the surface pressure in the cases with the different serrated trailing edge in present.