Study of propagating acoustic sources in a fan intake by modal analysis of tone noise
Abstract
A new data processing scheme was developed for computing azimuthal wave-number spectra of noise generated in circular or annular ducts; in this method, positive and negative modes are separated. Examples are presented demonstrating that this method makes it possible to characterize the fan or compressor acoustic sources and duct linings. Moreover, the parasitic effects of flow distortions, due to deficiencies of static test benches, can be clearly distinguished and thus can be eliminated from the results.
- Publication:
-
ONERA
- Pub Date:
- 1988
- Bibcode:
- 1988inno.confQ....L
- Keywords:
-
- Acoustic Ducts;
- Modal Response;
- Noise Propagation;
- Noise Spectra;
- Compressors;
- Engine Noise;
- Fans;
- Turbojet Engines;
- Wave Propagation;
- Acoustics