Experimental study of airfoil-rotor interaction noise by wavelet beamforming

Abstract

A wavelet-based beamforming method is performed in this investigation to analyze moving acoustic sources in the time-frequency domain, which is of scientific significance and practical importance. The particular problem considered here is the interaction noise from an airfoil and the downstream rotor in the presence of a moving flow, which could find realistic applications in next-generation underwater and aviation systems. A realistic experimental setup is prepared with a rotating blade and the airfoil in an anechoic wind tunnel. The results show that the wavelet-based beamforming method is very suitable for unsteady sound source imaging, which would be able to strengthen the time-frequency analysis capability of acoustic imaging tests and, consequently, possibly leads to deepened physical insights of various transient and moving systems in underwater and aerospace systems.