Aerofoil self-noise radiations subjected to serration flap angles

Abstract Besides the investigation of aeroacoustics responses an asymmetric aerofoil subjected to serrated trailing edge flap angles from negative (flap-down) positive (flap-up), this paper also provides a new perspective on physical mechanisms broadband noise reduction by edge. The blade-loading effect, which is function length and angle for straight/non-serrated flat plate, plays considerable role in self-noise radiation that hitherto less recognised. When same plate cut into sawtooth serration shape, will be underpinned simultaneously both effect (dominant) effect. results demonstrate far-field can manipulated significantly depending direction angle. In flap-down configuration, become factor causes deterioration performance across entire frequency range. flap-up three spectral frequencies zones defined. At low-frequency zone, diminished cross-flow at gaps impede capability. central-frequency re-distribution turbulence sources spanwise scales enhance performance. Improvement achieved high-frequency zone owing lack interaction between structure. A concept positively demonstrated varying as periodic (spanwise wavy serration). compared non-flap edge, found further increase level central regions. Graphic abstract