Noise Validation of Model Fan Rig with Engine

In this paper, the measured noise characteristics of a 1/3 scale aeroengine turbofan are compared with tests with a c ylindrical intake and a drooped intake more realistic of the aeroengine. The differences in noise are discussed and explained with the help of circumferential mode detection in the fan intake. The noise from the rig with a drooped intake is then compared to the noise from a full scale statically tested aeroengine after suitable scaling and correction factors were applied. Good agreement was achieved except at low frequencies where the comparison was compromised by the engine jet noise.