Synchronous impact phenomenon of a high-dimension complex nonlinear dual-rotor system subjected to multi-frequency excitations  

作　　者：LIN RongZou HOU Lei DUN ShiWei CAI YuFeng SUN ChuanZong CHEN YuShu 

机构地区：[1]School of Astronautics,Harbin Institute of Technology,Harbin 150001,China [2]Factory of Xiangyang Hang Tai Power Machinery,Xiangyang 441000,China [3]School of Mechanical Engineering,Shenyang University of Technology,Shenyang 110870,China

出　　处：《Science China(Technological Sciences)》2023年第6期1757-1768,共12页中国科学（技术科学英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.11972129);the National Major Science and Technology Projects of China(Grant No.2017-IV-0008-0045);Department of Science&Technology of Liaoning Province(Grant No.2019BS182);the Educational Department of Liaoning Province(Grant No.LJGD2019009)。

摘　　要：The“synchronous impact”is a phenomenon that increases the dynamic load of the inter-shaft bearing,when the frequency of the aerodynamic excitation is close to the contact frequency of the inter-shaft bearing.This work addresses the“synchronous impact”phenomenon of an aero-engine.The 104 degree-of-freedom dynamical model of an aero-engine is established by the finite element method,in which the complex nonlinearity of the Hertzian contact force of the inter-shaft bearing with clearance is included,and the multi-frequency excitations such as the unbalanced excitations of the high-and low-pressure rotors and the aerodynamic excitation are considered.A harmonic balance method combined with the alternating frequency time-domain method(HB-AFT)is introduced to obtain periodic responses of the high-dimension complex nonlinear dual-rotor system.The results show that there emerges a peak value of the amplitude-frequency response for the contact frequency harmonic component of the outer ring of the inter-shaft bearing,when the aerodynamic excitation frequency is close to the contact frequency.In addition,the dynamic load of the inter-shaft bearing increases significantly.Moreover,the parametric analysis shows that the“synchronous impact”phenomenon is sensitive to the change of the speed ratio of the high-and low-pressure rotors.The dynamic load of inter-shaft bearing can be significantly reduced by changing the speed ratio by 1%.The results obtained in this paper not only provide more insight into the mechanism of the“synchronous impact”phenomenon but also demonstrate the HBAFT method as a potential semi-analytical tool to explore the high-dimension complex nonlinear system.

关 键 词：synchronous impact DUAL-ROTOR inter-shaft bearing HB-AFT multi-frequency excitations 

分 类 号：V231.96[航空宇航科学与技术—航空宇航推进理论与工程]