Numerical Investigation on Change of Airframe Noise by Flap Side-edge Shape

Abstract

This paper presents computational and experimental studies on the flap side-edge noise using a three-element rectangular high-lift wing model with a full-span slat and a part-span flap for high-lift device noise research in JAXA. The main purpose of this paper is focused on the numerical investigation of change of the flowfield and far-field noise by the flap sideedge shapes. Several flap side-edge configurations with rounded flap side-edges, a cavity side-edge, and a protruding-type device on the lower surface of flap are investigated in this paper. By the computations and wind tunnel tests, mechanisms of the noise generation and reduction of flap side-edge noise are discussed.