Study on algorithms of acoustic emission source localization in complicated environment

When locating the rub-impact source of rotating machines by acoustic emission technology, precise time-difference of arrival is always not available to calculate the faults location due to the deteriorated signal correlation relationship among different sensors. This is caused by both the dispersion phenomenon since the acoustic emission signal includes various waveform modes while each type of waveform has different velocity in the complex rotor structure and intense noise influence inner the device. To solve this problem, generalized cross correlated time delay estimation (GCC-TDE) is introduced to calculate the time difference of arrival of emission signals. Segment correlation is adopted on the homologous emission signals of two sensors to resolve the no-peak problem in conventional correlation resulted from waveform distortion. The experiments showed that GCC-TDE of the acoustic emission signal in complex structure can reach satisfied results and correlation performance has been improved by segment correlation, thus enables higher location precision.