A Cyclostationary Approach in Extracting Modulation Feature from Fan Vibrations

Experimental Methods for Localizing / Characterizing Sources

Vibration signals related to fan aerodynamic performance are generally transient, non-stationary and non-linear. To extract aerodynamic-related features from these complicated signals, this paper presents an improved cyclostationary approach and employs an enhanced envelop spectrum to detect the modulating, harmonic and coupled frequencies, as well as to reconstruct principle modulating intensities. These modulation-related components have strong links with the flow-induced excitation, and can provide an alternative way to reveal the fan aerodynamics. Finally proposed approach is validated by typical simulation and axial-flow fan experiments.