Experimental Investigation of Vibration Characteristics in a Centrifugal Pump with Vaned Diffuser

Abstract

In order to investigate the vibration characteristics of centrifugal pump, a centrifugal pump with vaned diffuser whose specific speed is 190 was chosen for this research. Both the experiments of energy performance and vibration characteristics of the pump were performed. The results indicate that when flow rate of the pump is 270 m3/h, the head is 15.03 m and the efficiency is 71.47%. The maximum efficiency is 71.71% when the flow rate of the pump is 233 m3/h and the head is 16.92 m. And a wide frequency band of vibration appears at 600 Hz at outlet flange of the pump. The vibration intensity at the outlet flange is largest. The vibration intensities at both sides of bearing casing are slighter than those at outlet flange and larger than those at motor base. The vibration intensity at the motor base is larger than that at pump base, and the vibration intensity at the pump body is the lowest. The vibration intensity of monitoring point M4 in the X direction under 0.8Qd is 1.27 mm/s, which is the maximum under three flow rates.

Experimental Analysis on Pressure Fluctuation Characteristics of a Centrifugal Pump with Vaned-Diffuser

“…With the development of science and technology, hydraulic performance, operation stability and reliability of centrifugal pumps with a vaned-diffuser are given increasing attention. Wang et al [1][2][3] numerically improved a centrifugal pump with vaned-diffuser by using of trimming back-blades of impeller and smoothing sharp corner in annular chamber to enhance efficiency of the pump, and accomplished experiments focusing on energy performances and vibration characteristics to verify the effectiveness of the improvement results. Guo et al [4] implemented experimental measurement of pressure fluctuation (PF) and the vibration of impeller of centrifugal pump with a vaned-diffuser.…”

Efficiency improvement and evaluation of a centrifugal pump with vaned diffuser

“…In recent years, some scholars have performed a lot of research on the vaned diffuser of the centrifugal pump by experiment and numerical simulation. [14][15][16][17][18] Sun et al 19 analyzed the pressure fluctuations in a pump turbine with different guide vane's opening angle and found that pressure fluctuation under design-opening angle were much lower than those under off-designopening angle. The main source of pressure fluctuation between runner and guide vanes is rotor/stator interaction.…”