caa a22 4500 445360283 CHVBK 20180317142913.0 cr unu---uuuuu 170323e20110501xx s 000 0 eng 10.1007/s11071-010-9858-4 doi (NATIONALLICENCE)springer-10.1007/s11071-010-9858-4 Effects of flexible support stiffness on the nonlinear dynamic characteristics and stability of a turbopump rotor system [Elektronische Daten] [Changqing Bai, Qingyu Xu, Jiyan Wang] Using a flexible support is an efficient approach to solving the subsynchronous problems in a turbopump. In this paper, nonlinear rotordynamic analysis of a liquid fuel turbopump with a flexible support is presented using a dynamic modeling including two key destabilizing factors, nonlinear hydrodynamic forces induced by seals and internal rotor damping. The methodology of the partitioned direct integration method (PDIM) is described for reducing the computational efforts efficiently. Combining the PDIM and the shooting method, a nonlinear stability analysis of the rotor system is performed effectively. The numerical results, which are in good agreement with test data, indicate that the effects of flexible support stiffness k on the dynamic characteristics and stability of the rotor system are significant. The first critical speed of the rotor system rises as a nonlinear function of k markedly. The second critical speed varies slightly and approximates a linear variation as k increases. The onset speed of instability of the rotor system rises initially and then reduces as k increases. The effect of seal nonlinearities at low k is contrary to that at high k and the effect of seal length on the system stability is more significant than that of seal radius. The results explain the nature of the subsynchronous motion of a turbopump rotor system with flexible support and can be used in the design and operation of a liquid fuel turbopump rotor system to eliminate its rotordynamic problem. Springer Science+Business Media B.V., 2010 Turbopump nationallicence Flexible support nationallicence Seal nationallicence Internal damping nationallicence Nonlinear stability nationallicence Rotordynamic nationallicence Bai Changqing School of Aerospace, Xi'an Jiaotong University, 710049, Xi'an, China aut Xu Qingyu School of Aerospace, Xi'an Jiaotong University, 710049, Xi'an, China aut Wang Jiyan School of Science, China University of Mining and Technology, 221008, Xuzhou, China aut Nonlinear Dynamics Springer Netherlands 64/3(2011-05-01), 237-252 0924-090X 64:3<237 2011 64 11071 https://doi.org/10.1007/s11071-010-9858-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11071-010-9858-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Bai Changqing School of Aerospace, Xi'an Jiaotong University, 710049, Xi'an, China aut NATIONALLICENCE 700 1- Xu Qingyu School of Aerospace, Xi'an Jiaotong University, 710049, Xi'an, China aut NATIONALLICENCE 700 1- Wang Jiyan School of Science, China University of Mining and Technology, 221008, Xuzhou, China aut NATIONALLICENCE 773 0- Nonlinear Dynamics Springer Netherlands 64/3(2011-05-01), 237-252 0924-090X 64:3<237 2011 64 11071 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer