A Review on the Flow-Induced Excitation Mechanism of Centrifugal Pumps During Off-Design Conditions

Abstract

In thermal power plants, both cooling water and boiler feedwater need to be delivered by centrifugal pumps. When centrifugal pumps operate under off-design conditions, significant flow-induced vibration problems often arise due to the complex unsteady flow inside, which in turn affects their operational reliability and service life. This paper presents a comprehensive review of flow-induced vibration issues in centrifugal pumps under off-design operating conditions and the corresponding mitigation methods. Existing studies indicate that off-design unsteady flow phenomena constitute the primary drivers behind pressure fluctuations and vibrational noise. Current countermeasures for mitigating flow-induced vibration encompass structural optimization approaches: refining the impeller-volute gap, adjusting the trailing edge structure of blades, and modifying blade count. Nonetheless, existing research remains deficient in in-depth exploration of the intrinsic correlations between unsteady flow behaviors and vibrational noise, alongside targeted suppression strategies for off-design scenarios. Future investigations ought to more precisely elucidate how flow field properties affect pressure pulsation, and establish a comprehensive quantitative characterization framework for unsteady flows, these efforts will facilitate the advancement of design theories and methodologies for centrifugal pumps with low vibration and noise emissions.