Aeroacoustic effects of a cylinder-plate configuration

Abstract

Aerodynamically generated noise can be amplified enormously by the insertion of a plate behind a cylinder. In this work, the aeroacoustic sound generation of a cyliner-plate configuration placed in a steady flow has be investigated experimentally. The amplification of the generated sound is quantified, and the condition for the amplification is analyzed in detail. In the experiments, the distance between cylinder and plate as well as the flow velocity were varied. A critical spacing that depends on the Reynolds number was found, for which the sound pressure levels rise dramatically. The variation of the distance and the flow velocity also showed a hysteresis effect regarding the occurance of the sound-pressure amplification.