An experimental investigation on the near-field turbulence and noise for an airfoil with trailing-edge serrations

This study concerns the mechanisms of the turbulent broadband noise reduction for an airfoil with the trailing edge serrations. The turbulence spatio-temporal information were measured with 3D hot-wire and the noise results were acquired with a line array. The experiment is carried out in the Northwestern Polytechnical University low speed open jet wind tunnel on the SD2030 airfoil. λ/h = 0.2. It is showed the spreading rate of the wake and the decay rate of the wake centerline velocity deficit increased with serrated edge compared to the straight edge, shedding vortex peaks appeared in the wake, and the three components of velocity changed differently with serrated trailing edge. Serrated trailing edge structure could reduce the radiated noise was proofed by noise results.