Abstract：To investigate the effect of fluid excitation force on the dynamic response of screw centrifugal pump rotor system, a single blade screw centrifugal pump was used as research object. The internal flow field of pump was calculated by CFX 14.5,and the variation of radial force of impeller with time under different flow conditions was obtained. The finite element model of the rotor system was established, and the critical speed and the mode of rotor were analyzed. The transient response of the rotor system was investigated when the radial force was used as external excitation under different flow conditions. The results show that the radial force of impeller is cyclical under different flow conditions, and the period is the same as that of impeller. The radial force can be decomposed into constant amount and pulsation amount, and the pulse peak is gradually decreased with the increasing of frequency. At designed speed, the rotor system does not resonate. When the effect of radial force is considered, the radial displacement at the monitoring point of impeller presents complex periodic changes, and the frequency component of radial force is reflected in the vibration process.
2018, Vol. 39 
