中文摘要：

立式多级离心泵在实际工作中．液态工作介质属性会影响泵的振动特性。甚至导致临界转速值下降引发共振等严重振动事故。文中以某型多级离心泵转子为研究对象，探讨工作介质与泵转子结构的力学关系，推导带有工作介质的泵转子动力学方程．将工作介质质量分解为转子附加质量、壳体附加质量和液体耦合质量，建立含工作介质的立式多级离心泵和电机转子系统动力学模型．计算系统临界转速与振型．总结出不同工作介质属性对泵转子振动特性的影响规律。研究结果表明：工作介质对离心泵转子振动特性的主要影响取决于转子附加质量、壳体附加质量、液体耦合质量的3部分质量的约束；工作介质密度对第1阶临界转速影响较大，且随着介质密度增大，临界转速值降低，与工作转速隔离裕度变小。这些可为立式多级离心泵转子动力学设计和振动故障诊断分析提供参考。

英文摘要：

On the vertical multistage centrifugal pump actual working condition, the liquid working medium has a certain mass to affect the pump vibration feature, and even lead to the resonance due to the drop of natural frequency. A vertical multistage centrifugal pump rotor was taken as an example to discuss the mechanical relationship of pump rotor with working medium. The pump with working medium dynamic equations was deduced. A dynamic finite element model for the multistage centrifugal pump with working medium, working medium mass was decomposed into rotor added mass, housing added mass and fluid coupling mass as constraints, was built up in this paper. The critical speeds and shape mode were analyzed based on the dynamic model. The effects of different working medium properties on centrifugal pump vibration characteristics are obtained, it is shown that the effect of working medium on pump depends on the three constraints including rotor added mass, housing added mass and fluid coupling mass, respectively. The density of working medium mainly affects the first order critical speeds values, and with the increasing working medium density, the isolative interval between critical speeds and the working speed become smaller due to the critical speeds reduction. This article can be provided some advises to vertical multistage centrifugal pump rotor dynamic design and analysis of the vibration fauh diagnosis.