Crack Detection in Operating Rotors using Directional Harmonic Wavelet Transform
نویسندگان
چکیده
In this paper, a new tool for crack detection in operating rotors based on wavelet theory is described. Customarily, two approximate methods of spectral analysis, i.e. ShortTime Fourier transform and Wigner distribution, have been used to analyse the vibration components of cracked rotors during run-up or run-down periods. However, for both methods, high resolution cannot be achieved simultaneously in both the time and frequency domains. To overcome this limitation, the Directional Harmonic Wavelet Transform (DHWT) technique has been developed based on the harmonic wavelet transform theory. Using this method, measured vibration data of a cracked rotor system have been analysed and promising results have been obtained with this method as the crack related subharmonic resonances could be clearly identified. NOMENCLATURE : time : signal : : speed of rotation : frequency of vibration : wavelet coefficient : scaling function : harmonic wavelet function
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