Acoustic Resonance Phenomena In High Energy Variable Speed Centrifugal Pumps

Abstract

The design of reliable pumps is of the utmost importance in petrochemical and power installations. Downtime can be costly in terms of lost production and in the power industry loss of generating capability. In order to meet this challenge, it is necessary to use state-of-the-art engineering design and analysis capabilities. In recent years, it has been necessary to design pumps at relatively high energy levels capable of operating over a wide range of flow conditions and speeds. Due to impeller vane and volute lip intersection, hydraulic pulses are generated at vane passing frequencies. If the pulse frequency corresponds to an acoustic resonance, the pulse may be amplified by as much as 100 times. The resulting large pressure pulsations interact with the pump rotor to cause unacceptable vibration levels. Variable speeds pumps are particularly susceptible, since they can create pulsations over a wide range of speeds.