EXPERIMENTAL DETERMINATION OF THE RUBBING LOCATION BY MEANS OF ACOUSTIC EMISSION AND WAVELET TRANSFORM

A method to pinpoint the rubbing location in a rotor-bearing system is presented. This method is based on the data sampled by acoustic emission (AE) sensors placed at different bearing supports. Usually, the point where rubbing occurs cannot be detected using the method of cross-correlation directly to the data, due to the noise produced during rubbing and the structure resonance of the signal. Through wavelet transform (WT), signals are decomposed into a series of time-domain signals, each of which covers a specific octave frequency band. Then the method of cross-correlation is applied to the decomposed signals to detect the rubbing location. This method is found to be very effective.