Acoustic time delays across a free-jet shear layer are measured and compared with predictions based on (i) ray paths refracted abruptly across a cylindrical vortex sheet and (ii) ray paths traced through a more realistic diverging flow model. The close agreement between measurement and theory confirms that Snell's law provides an accurate prediction of wavefront refraction or angle changes across a diverging shear layer. Microhpones are placed on calculated ray paths to determine the coherent transmission and internal reflecion characteristics of the shear layer and also the scattering of sound by the shear-layer turbulence. The transmission data essentially verify the proposed, theoretical calibration factor which forms part of a computational procedure that is being developed to convert model jet data from a free-jet facility to inflight conditions. (Kursetz)
Experimental study of transmission, reflection and scattering of sound in a free-jet flight simulation facility and comparison with theory
Experimentelle Untersuchung der Uebertragung, Reflektion und Streuung von Schall bei der Simulation eines Freistrahles unter Flugbedingungen mit einem Vergleich der theoretischen Werte
AIAA-Papers ; 1-16
1977
16 Seiten, 32 Bilder, 1 Tabelle, 6 Quellen
Aufsatz (Konferenz)
Englisch
Experimental Facility for the Complete Determination of Sound Transmission in Turbochargers
SAE Technical Papers | 2010
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