A Comparison of the Cavitation Monitoring of a Centrifugal Pump Using Vibration and Acoustic Methods

摘要

Cavitation in a centrifugal pump causes deterioration of the hydraulic performance, damage to the pump components, high vibration and load noise. To prevent cavitation and maintain pump performance, it is necessary to detect and diagnose the cavitation as accurately as possible. This paper presents non-intrusive approaches to the detection of cavitation using structure vibration and airborne acoustics. Based on the understanding of cavitation, higher turbulent flow will result in a higher dynamic pump load, the vibration and acoustics data are measured close to the discharge port and are analysed in both the time and frequency domain. It has been found that the amplitude ratio between high frequency band and overall frequency band can be a good indicator for the detection and quantification of the cavitation. Both the vibration and acoustics measurements need the same effort in data management including data collection and processing. Both of them also have equal capability for the detection. However, the acoustic sensor is easier to install due to its capability of remote sensing.