The present paper describes the use of microphone array technology and beamforming algorithms for the measurement and\r\nanalysis of noise generated by the interaction of a turbulent flow with the leading edge of an airfoil. Experiments were performed\r\nusing a setup in an aeroacoustic wind tunnel, where the turbulent inflow is provided by different grids. In order to exactly\r\nlocalize the aeroacoustic noise sources and, moreover, to separate airfoil leading edge noise from grid-generated noise, the\r\nselected deconvolution beamforming algorithm is extended to be used on a fully three-dimensional source region. The result\r\nof this extended beamforming are three-dimensional mappings of noise source locations. Besides acoustic measurements, the\r\ninvestigation of airfoil leading edge noise requires the measurement of parameters describing the incident turbulence, such as the\r\nintensity and a characteristic length scale or time scale. The method used for the determination of these parameters in the present\r\nstudy is explained in detail. To demonstrate the applicability of the extended beamforming algorithm and the experimental setup as\r\na whole, the noise generated at the leading edge of airfoils made of porous materials was measured and compared to that generated\r\nat the leading edge of a common nonporous airfoil.
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