Nonlinear dynamic behavior of a flexible asymmetric aero-engine rotor system in maneuvering flight  

作　　者：Tian GAO Shuqian CAO Yongtao SUN 

机构地区：[1]Department of Mechanics,Tianjin University,Tianjin 300354,China [2]Tianjin Key Laboratory of Nonlinear Dynamics and Control,Tianjin 300354,China [3]National Demonstration Center for Experimental Mechanics Education,Tianjin University,Tianjin 300354,China

出　　处：《Chinese Journal of Aeronautics》2020年第10期2633-2648,共16页中国航空学报（英文版）

基　　金：the National Key Basic Research Program of China(No.2015CB057400);the National Natural Science Foundation of China(Nos.11672201 and 11872045);the Major Special Basic Research Projects for Aeroengines and Gas Turbines(No.2017-IV-0008-0045)。

摘　　要：Aero-engine rotor systems installed in aircraft are considered to have a base motion.In this paper,a flexible asymmetric rotor system is modeled considering the nonlinear supports of ball bearings and Squeeze Film Dampers(SFDs),and the dynamic characteristics of the rotor system under maneuvering flight are systematically studied.Effects of the translational accelerative motions,the angular motions and the pitching flight with combined translational and angular motions on nonlinear dynamic behavior of the rotor system are investigated.The results show that,due to the nonlinear coupled effects among the rotor,ball bearings and SFDs,within the first bending resonance region,responses of the rotor show obvious nonlinear characteristics such as bistable phenomenon,amplitude jumping phenomenon and non-synchronous vibration.Translational acceleration motion of the aircraft leads to axis offset of the rotor system and thus results in the reduction and the final disappearance of the bistable rotating speed region.The pitching angular motion mainly affects rotational vibration of the rotor system,and thus further induces their transverse vibrations.For the pitching flight with combined translational and angular motions,a critical flight parameter is found to correspond to the conversion of two steady responses of the rotor system,in which one response displays small amplitude and synchronous vibration,and the other shows large amplitude and non-synchronous vibration.

关 键 词：Aero-engine rotor system Ball bearings Maneuvering flight Nonlinear dynamics Squeeze film dampers 

分 类 号：V231[航空宇航科学与技术—航空宇航推进理论与工程]