Original Paper

Journal of Engineering Research

, 3:38

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

Numerical research on dynamic lateral vibration of a pumpturbine’sshaft system

  • Wen-Jie ZhouAffiliated withInstitute of Process Equipment, Zhejiang University Email author 
  • , Xue-Song WeiAffiliated withInstitute of Process Equipment, Zhejiang UniversityFaculty of Engineering, Kyushu Institute of Technology
  • , Guang-Kuan WuAffiliated withInstitute of Process Equipment, Zhejiang University
  • , Wan-Jiang LiuAffiliated withHarbin Institute of Large Electrical Machinery
  • , Le-Qin WangAffiliated withInstitute of Process Equipment, Zhejiang University


The novel transient dynamic vibration model of pump-turbine’s shaft system considers nonlinear seal fluid forces, in addition to the coupled effects of unbalanced magnetic pull (UMP), guide bearing force, unbalanced mass force and hydraulic force. The calculations are based on the finite element method (FEM) and Lagrange equation. Node automation division method (NADM) is developed in-house for quick and accurate node division. The differential equations of motion and the dynamic response of the unit are resolved by implicit Newmark method. The nonlinear dynamic characteristics of crown seal force and UMP are researched. The transient and steady lateral vibrations of three bearings are also analyzed using the periodic response diagrams, steady axis orbits and waterfall diagrams. The calculated results demonstrate that the mounted eccentricity, crown seal channel clearance and air-gap length have significant effects on the dynamic vibration of the shaft system. When the mounted eccentricity is 0mm, clearance of crown seal is 3mm, air-gap length is 35mm, the stability of the system is the highest. Both quantitative and qualitative results are relevant for engineering use in pump-turbine’s shaft system design.


Finite element method (FEM) Newmark method node automation division method (NADM) transient nonlinear seal forces