Experimental study of noise generated by porous trailing-edges on owl-inspired aircraft

A modular porous edge is designed for a radio-controlled aircraft and is tested to assess its effectiveness as a passive noise control strategy on flying vehicles. The porous edge draws inspiration from one of the plumage adaptations of owl, the tattered fringe along the back edge of the wing, which is thought to mitigate turbulence sound scattered by the trailing edge. The testing platform is designed to measure surface pressure fluctuations from interchangeable porous and non-porous surfaces, where the wing self-noise is measured by a microphone on the fuselage, as would be perceived by an owl in flight. Analysis of the effects of wing porosity on the local turbulent flow over the wing and on the radiated aerodynamic noise will be presented together in comparison with existing theoretical predictions for porous edge noise reduction.