Noise Source Location in Turbomachinery Using Coherence Based Modal Decomposition
FITZPATRICK, JOHN AIDAN
Metadata:Show full item record
Citation:Gareth J. Bennett, Ciaran O'Reilly, Ulf Tapken, John Fitzpatrick, Noise Source Location in Turbomachinery Using Coherence Based Modal Decomposition, 15th AIAA /CEAS Aeroacoustics Conference, Miami, Florida, 11-13 May 2009, 2009
Coherence based source analysis techniques can be used to identify the contribution of turbomachinery core noise sources to pressure measurements in the far-field. The usual approach is to locate a measurement sensor within the engine and to calculate the ordinary coherence function between this and the far-field pressure measurement. If the internal measurement is close to a dominant noise source, the technique will identify this sources? contribution to the overall far-field energy. Modal decomposition is an advanced technique which can provide detailed information as to the modal content of sound propagating in ducts. When applied to aero-engines, the technique can be used as a diagnostic to determine which of the many rotor-stator stages contribute most to the overall radiated sound power. The method developed in this paper discusses how the two techniques can be combined to locate the plane at which a mode is generated within an aeroengine. A proof of concept of the technique is successfully demonstrated with the use of simulated data.
Other Titles:15th AIAA /CEAS Aeroacoustics Conference
Keywords:Mechanical & Manufacturing Engineering