Aerodynamic noise measurement in anechoic wind tunnel of rod-airfoil with leading edge serrations

Abstract

Turbulent flow interaction with the leading edge of an airfoil generates a well-known leading edge noise. The present work is an experimental investigation of reducing the leading edge noise by adapting serrations on the leading edge of NACA0012 airfoil. A rod is placed upstream of the airfoil to magnify the turbulence flow-leading edge interaction. Locations and the size of the serrations are two parameters being investigated for the noise reduction. The study found that a noise reduction up to 3.5 dB is obtained when the size of the serration is wider. Additionally, more sound reduction can be obtained when the angle of attack is increased.