离心泵作透平壳体模态分析

离心泵反转作透平是一种回收液体余压能的理想方法,泵壳的模态分析对泵作透平的振动性能至关重要.为了掌握泵作透平下,壳体模态对振动激发噪声辐射规律的影响,验证泵壳有限元模型的准确性,针对离心泵泵壳结构特点设计并搭建了模态试验台,采用捶击法对泵壳进行了试验模态分析,对离心泵壳体进行三维建模与有限元分析,进行试验与数值分析结果的对比.结果表明:壳体各阶模态均为独立模态,且相互正交,可认为试验模态识别精度得到检验,试验模态结果具有较高的可信度.建立的有限元模型能够较好地反映实际结构的动态特性,可用于基于模态求解的振动辐射噪声特性分析.

Modal analysis of centrifugal pump casing under pumps as turbines

The PAT(pumps as turbines)is one of the best alternatives for energy recovery,and the modal analysis of pump casing has a crucial effect on the vibration performance of PAT. In order to grasp the effect of noise caused by vibration under different pump casings and testify the accuracy of the element model of pump casing, the present work is to analyze the pump casing modal by hammering under the condition of pumps as turbine. The modal experiment platform is established for meeting the feature of pump casing. The reliability and accuracy of experiment plan are achieved through experimental modal analysis. From the comparison between the numerical analysis under the three-dimensional model of pump casing and experimental results, each modal of casing is independent and orthogonal, which means that the accuracy of the experiment is obtained. The result also shows that the finite element model of pump casing can better reflect the dynamic characteristics and can be used to analyze the noise induced by vibration.