Concept, design and characterization of a small aeroacoustic wind tunnel facility with application to airfoil measurements

Experimental investigation of flow-induced sound and sources of sound necessitates an adequate environment of low interfering noise and suppression of unwanted sources of sound. In order to investigate the sound from fluid-structure interactions, a low-noise wind tunnel has been designed and implemented. This paper gives an overview of the design criteria and specifications, along with an aeroacoustic and aerodynamic characterization of the facility. The suitability to airfoil self-noise studies is explored and first measurements with a model airfoil are presented. The paper concludes with an outlook on future applications.

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