Abstract：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.
2013, Vol. 32 
