05 - Propulsion
STUDY OF NON-ROTATING MICROPHONE ARRAY FOR SPINNING DUCT MODE DETECTION
J.Y. Ying¹, X.B. Wang¹, J. Kang¹, M.H. Lu¹; ¹AECC commercial Aircraft Engine Co.,Ltd., China
This paper presents a method using non-rotating microphone array to detect spinning duct modes of any section in fan duct. The numerical acoustic propagation model is applied to build up the transfer function between the acoustic source section to the fixed microphone array, the system identification tools is applied to calculate the duct mode factors based on the numerical transfer function and the measured response of microphone array.