Noise reduction by local application of porous material within the aeronautical context

Abstract

Besides the noise produced by aircraft engines, airframe noise is important, or even dominant, in certain flight phases, e.g., landing phase. Airframe noise can be defined as sound generated by the interaction between a turbulent flow and the aircraft’s geometry (e.g., landing gear noise, flap side-edge noise, or noise generated at a wing’s trailing edge). In this numerical contribution, the local application of porous material is reviewed for the reduction of the sound produced by the wing’s trailing-edge.Local application here means substituting the latter part near the wing’s trailing-edge with a porous insert. The considered wings consist of symmetric and asymmetric profiles, as well as one with a highly deflected flap. Results are presented and the advantages/disadvantages of noise reduction by porous material are discussed. Note that this proceeding by far does not give a complete overview, but a coloured one influenced by the past re-search efforts of the authors