Various means can be used to vary engine inlet throat areas in order to reduce noise generated at takeoff and approach. Low-speed wind-tunnel tests were performed to evaluate the aeroacoustic performance of two takeoff geometries (cylindrical centerbody and bulb-shaped centerbody) and four approach geometries (bulb-shaped centerbody, annular ring, radial vanes, and step diffuser). The effects of inlet internal lip shape and diffuser length on sonic inlet performance were also investigated. It was found that the single-passage geometries, in particular a cylindrical centerbody takeoff geometry and a bulb-shaped centerbody approach geometry, provide the highest level of aeroacoustic performance. Increasing the inlet lip contraction ratio extends the maximum incidence angle for attached lip flow, while increasing the inlet diffuser length increases total pressure recovery for a given amount of noise suppression.
Aeroacoustic performance of scale model sonic inlets
American Institute of Aeronautics and Astronautics, Aerospace Sciences Meeting ; 1975 ; Pasadena, CA
1975-01-01
Conference paper
No indication
English
Aeroacoustic performance of scale model sonic inlets
AIAA | 1975
|Aeroacoustic performance of scale model sonic inlets
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