The Boeing Commercial Airplane Company and the Pratt and Whitney Aircraft Group have been engaged in a cooperative program to develop improved static noise testing techniques to decrease the observed acoustic differences between static and flight engine testing. Differences in atmospheric turbulence levels and inlet inflow distortions were identified as key problems in simulating flight noise mechanisms statically. Large scale inflow control structures, consisting of screens and flow straighteners were designed, built, and evaluated by both companies using a JT9D-7 engine and compared against Boing 747 flight test data. The results show that the devices functioned effectively in reducing noise generated by rotor-inflow distortions, resulting in an improved method for simulating in-flight noise characteristics. (Krautzig)
The development of inflow control devices for improved simulation of flight noise levels during static testing of a HBPR turbofan engine
Die Entwicklung von Ansaugkontrollgeraeten zur verbesserten Simulation von Fluglaermpegeln bei statischen Tests eines HBPR-Turbofan-Motors
AIAA-Papers ; 1-11
1980
11 Seiten, 25 Bilder, 1 Tabelle, 9 Quellen
Conference paper
English
Turbofan-engine noise suppression
AIAA | 1966
|Turbofan-engine noise suppression
AIAA | 1967
|