Nonlinear Dynamic Stability and Bifurcation of Turbo Pump-Labyrinth Seal Rotor System
Xia Fuqiang(1,2),Li Songtao(1),Xu Qingyu(1)
(1 Department of Architectural Engineering and Mechanics, Xi’an Jiaotong Univer sity,Xi’an, 710049,China)
(2 Shenzhen Branch of Arup International consultants(Shanghai) Co.,ltd.,Shenzhen , 518026,China)

Abstract：The dynamic stability of an engineering labyrinth seal rotor system is investigated. Muszynska model is employed to describe the nonlinear force from the seals, and finite element method is adopted to evaluate the rotor system. The higher order nonlinear algebra equations are divided into lower order bulks to shorten the computational period greatly. The threshold speed can be found with Floquet theory and the unstable dynamic behaviors of the system are analyzed. The orbits of shaft are simulated via partitioned Newmark approach, and the effects of the two rotor disk unbalance on the dynamic characteristics of the rotor system are discussed in detail.
Keywords：turbo pump rotor，labyrinth seal，stability，partitioned Newmark method.