Analysis of vibration signals produced by the cavitation in centrifugal pumps using the Power Spectrum and Continuous Wavelet Transform

Abstract

The cavitation phenomena cause noise, vibration and instability in centrifugal pumps. Furthermore, the cavitation usually generates wear and material erosion of the rotor blades which decreases the hydraulic performance and the pump life. In this work, it will be studied the vibration components produced by the centrifugal pumps cavitation using the signal processing and statistical analysis. For this purpose, the vibration signals were measured in three directions, x, y and z using accelerometers near to the rolling bearing of the pump with and without cavitation. In this way, an analysis of the power spectrum was applied in order to identify which direction would be more sensitive to the presence of the cavitation in the pump. Subsequently, the Continuous Wavelet Transform was applied to the vibration signals in the time domain for analyzing the vibration components caused by the cavitation. The results proved that this methodology can serve as a tool of analysis and identification of vibration components caused by the cavitation in centrifugal pumps.