Journal of Fluid Mechanics

Gelot M.B.R. and Kim J.-W.

Acute tonal noise can be generated from an aerofoil which is undergoing an acoustic feedback mechanism between laminar-to-turbulent boundary-layer transition and sound waves scattered at the trailing edge. This paper demonstrates that the aerofoil tonal noise can be substantially reduced if the aerofoil is equipped with a serrated trailing edge. In particular, the mechanisms by which the noise reduction is achieved have been discovered and explained for the first time in this paper. This was due to the highly accurate numerical simulations undertaken by the authors on the UK national supercomputer ARCHER using an in-house code CANARD (Compressible Aerodynamics & Aeroacoustics Research coDe) developed at the University of Southampton. Funded by Vestas Wind Systems, this outcome and the ongoing work (a PhD project) will make a significant impact on the reduction of wind-turbine noise by means of serrated trailing edges aimed for the next-generation blade design.