Coherence Method for Noise Analysis of Multi Reduction Gear Box

A noise analysis based on coherence method has been developed and utilized as a diag - nostic tool for defect detection of a gear box. A case study has been carried out on a multiple reduction gear box and the emitted noise is measured during normal working environment thus the signals are subjected to external disturbing noise. Using the coherence method, the original signals are identified and further analysis is carried out using enhanced Campbell as well as Order-ratio diagrams. The results show that the coherence method is a powerful tool in noise analysis.