Spectrum Normalization Method in Vibro-Acoustical Diagnostic Measurements of Hydroturbine Cavitation
- 1 December 1996
- journal article
- Published by ASME International in Journal of Fluids Engineering
- Vol. 118 (4), 756-761
- https://doi.org/10.1115/1.2835506
Abstract
Full-scale vibro-acoustical diagnostic measurements of cavitation in four Francis 6 MW double runner turbines were performed. Two types of sensors were used—a hydrophone sensing waterborne noise at the pressure side of a runner and an accelerometer mounted at various points at the outer turbine casing, facing the runner’s pressure side. The correlation of noise and acceleration intensity with suction-side pressure fluctuations and runner position was checked. A simple but efficient method of spectrum normalization, which rejects the influence of the measurement set characteristics and vibro-acoustical characteristics of a turbine, was developed. The resulting spectra reveal the dependence of cavitation source strength on the turbine power as a function of noise or acceleration frequency.Keywords
This publication has 2 references indexed in Scilit:
- Detection of cavitation by acoustic and vibration-measurement methodsLa Houille Blanche, 1969
- Vibrations in Hydraulic Pumps and TurbinesProceedings of the Institution of Mechanical Engineers, Conference Proceedings, 1966