Nonlinear dynamic response analysis of dualrotorsupportcasing system
                                                                    ZHANG Yaotao, XU Kejun, QIN Haiqin
 (Department of Aviation Mechanical Engineering and Management in Qingdao Branch,Naval Aviation University, Qingdao 266041, China)

Abstract: Aiming at the problem of the aeroengine safe and reliable using, the rotational speed, rotor eccentricity and rotational speed ratio of an aeroengine dual rotor tester were studied. A simplified complete machine finite element model with high and low pressure rotor intermediate bearings and the elastic deformation of the casing was established, the validity of the theoretical model was evaluated by comparing the model with the data of a dual rotor system in the literature, the Newmarkβ numerical integration method was used for solving nonlinear dynamic responses of systems. The results indicate that the vibration response amplitude of high pressure rotor and low pressure rotor is distinct difference when the eccentric position is different. The amplitude response is complicated when the eccentricity is applied to the high pressure rotor part. The motion pattern of the rotor system is significantly influenced by the ratio of high and low pressure speed to rotation ratio, the system may do cycle, almost cycle or chaotic motion.

Key words: dualrotorsupportcasing system; nonlinear dynamic; the Poincare map; spectrum analysis