螺旋离心泵转子系统动态响应数值分析

为研究螺旋离心泵转子对流固耦合作用的动态响应信息，以ZJ200-25型双叶片螺旋离心泵为研究对象，利用CFD软件CFX12.1和有限元软件ANSYS Workbench对其进行了考虑流场变载荷和结构相互作用的两场交替联合求解。得到转子受到的激励力以及位移响应频谱特点，结果表明：叶轮受到流场变载荷激励，发生了弯曲及拉伸振动；叶轮径向位移随流量增大而减小，其主频率与径向力主频率同为48.3Hz，轴向力以低频随机波动为主，但轴向位移仅在200Hz以内有较明显的响应，且振幅随频率增加而减小；叶轮质心位移在低阶频率处的振幅不高，高阶频率的振幅逐渐减小，轴向及径向位移均没有振幅过大的情况出现，说明螺旋离心泵转子正常工作时未发生共振，稳定性良好。本文研究结果对螺旋离心泵转子系统的设计改良及振动分析具有一定的参考意义。

Numerical analysis on dynamic response of screw centrifugal pump rotor

In order to analyze the dynamic response of screw centrifugal pump rotor to effect of Fluid-structure interaction, a ZJ200-25 screw type centrifugal pump with double screw blades was chosen as the study subject. The two-way coupling method was established to study the dynamic response of impeller under the fluctuating load in flow field of the pump. CFX12.1 and ANSYS Workbench were used to the FSI combined calculation for turbulent flow and structure response of impeller under several operating conditions. Exciting force and displacement frequency spectrums of impeller were obtained from the simulation calculation. The results showed that the rotor was bending and mechanical vibration under the fluctuating load from flow field. Impeller radial displacement decreases with the flow rate increase, and the displacement dominate frequency was equal to the radial force. Axial force fluctuated random in low frequency primarily, but the axial deformations only respond obviously within 200Hz, and the amplitude decreased with frequency increase. Impeller centroid displacement amplitude was not high in low frequency and decreased with frequency increase. There were no overlarge amplitude of axial and radial displacement, it is indicated that the rotor of the pump did not produce resonance at normal operation conditions. The conclusion obtained in this investigation will provide reference significance to the reformative design and master vibration characteristics of the screw centrifugal pump rotor system.