Experimental Study on Centrifugal Pump to Determine the Effect of Radial Clearance on Pressure Pulsations, Vibrations and Noise

This article represents experimental study work carried out on a single stage diffuser type centrifugal pump. The flow-induced pressure pulsations, mechanical vibrations and noise has been monitored during the experimentations for five different flow rates by varying the radial clearance. For each case of radial clearance and flow conditions, overall levels and frequency spectra, in a wide frequency range, have been examined. Vibration and noise both are predominantly due to the hydraulic effects. Impeller vane pass component has generally dominated the spectra. Frequency analysis revealed a good correlation in the overall vibration level and the overall noise level. In the frequency analysis, pressure pulsations are dominating at fundamental frequency and the impeller vane passing frequency. Also in the frequency analysis, level at fundamental frequency dominates the vibration spectra and level at vane passing frequency dominates the noise spectra. Experimental results show that by increasing the radial clearance between impeller and diffuser, lower pulsations, vibration and noise levels has been achieved. (Keywords— Centrifugal Pump, Mechanical Vibrations, Noise, Pressure Pulsations, Radial Clearance)