Measurements of Trailing-Edge-Noise Sources by means of Time-Resolved PIV

Abstract

The noise generation of turbulent flows at the trailing edges of airfoils is a general design problem and its importance increases in times of growing traffic. Turbulent boundary-layers being convected past the trailing edge into the wake are known to generate an intense, broadband scattering-noise. In this feasibility study the time resolved PIV technique was applied to a generic trailing-edge noise experiment as performed on a flat-plate model in the Aeroacoustic Wind Tunnel Braunschweig (AWB). Trailing-edge noise emission was measured simultaneously with instantaneous velocity vector-fields to relate the generated sound to the ensuing aeroacoustic source-quantities. The first step towards a new procedure for trailing-edge noise prediction, combining numerical methods with the time resolved PIV measurement, is presented.