Vibroacoustic Condition Monitoring of the Complex Rotation System Based on Multilevel Signal Processing

This work is devoted to further research and improvement of the vibroacoustic condition monitoring of complex rotation system during operation. The low-frequency vibration and acoustic noise in the range 0-10 kHz is used as diagnostic information. We propose to use Bispectrum (BS) Analysis at the first level of signal processing, and Fractal Analysis of BS contour images at the second level of signal processing for the diagnosis of small imbalance of rotation system. The experimental studies of forced vibrations of the physical model (PM) of the rotation system are carried out under steady-state and non-steady-state rotation excitations. The results of the BS Analysis of vibroacoustical signals, which are emitted by a rotating PM during different excitation modes, are processed in order to determine fractal box-counting dimension (Minkowski dimension). The research shows that a small imbalance can be efficiently detected by the proposed multilevel signal processing in all modes of PM operation.