Emphasizing on the envelope spectra of hydraulic turbomachinery vibration response towards cavitation diagnosis

Mousmoulis, Georgios and Anagnostopoulos, Ioannis and Aggidis, George and Gryllias, Konstantinos (2025) Emphasizing on the envelope spectra of hydraulic turbomachinery vibration response towards cavitation diagnosis. Measurement: Journal of the International Measurement Confederation, 241: 115733. ISSN 0263-2241

Text (MEAS-D-24-03652)
MEAS-D-24-03652.pdf - Accepted Version
Available under License Creative Commons Attribution.
Download (4MB)

Abstract

Cavitation attracts the interest of engineers who target the better understanding of its complex physics and the development of efficient detection tools. This research explores the effectiveness of vibration-based indicators in the prompt and effective diagnosis of cavitation initiating in the rotating flow fields of turbomachinery. The indicators are derived from the envelope spectra estimated with the use of Hilbert Transform, Spectral Kurtosis and Cyclic Spectral Correlation algorithms and data acquired from two semi-open impellers. By utilizing a transparent casing, the onset of cavitation can be observed, enabling the establishment of reliable criteria for evaluating the new indicators. Also, their applicability is assessed across a wide range of flow-rate and suction pressure conditions and in two different geometries. The results demonstrate the consistent ability of the indicators to exploit the high frequency carrier information related with the resonances excited from bubble implosions, to promptly and efficiently detect the phenomenon.