摘要
叶片-机匣碰摩严重影响航空发动机的性能、可靠性及安全性。考虑叶片-机匣碰摩、轴承非线性、联轴器不对中及高低压转子不平衡,利用有限元法建立双转子系统的非线性动力学模型;然后利用模态综合法缩减系统自由度,数值求解降阶模型的非线性振动响应,分析叶片-机匣碰摩故障响应特征。数值与实验结果表明:航空发动机双转子系统为多激励非线性系统,系统振动响应频率成分复杂,包括高低压转轴频率、多倍频、组合频率及其他复杂频率;当叶尖间隙较大时,叶片-机匣碰摩可能为局部碰摩,故障特征频率为叶片通过频率及其倍频,并在叶片通过频率两侧存在高低压转轴频率的调制边频带;当叶尖间隙较小时,叶片-机匣碰摩可能发生全周碰摩,呈现出由干摩擦引起的强烈自激振动。研究结果可为航空发动机双转子系统的叶片-机匣碰摩故障诊断及叶尖间隙设计提供一定参考。
Blade-casing rubbing have very important effect on the performance,reliability and safety of the aero-engine.A dynamic model of the dual rotor-bearing system of the aero-engine is established based on the Finite Element Method(FEM)by taking into account blade-casing rubbing,misalignment and nonlinearities of the rolling element bearings.The Component Mode Synthesis(CMS)method is applied to reduce the high-degrees of freedom of the dynamic model,and the nonlinear vibration responses of the reduced order model are analyzed by the numerical method to reveal the features of blade-casing rubbing.The results of simulation and experiment show that the dual rotor-bearing system of the aero-engine is a multi-excitation nonlinear system,which presents complex frequency components for the vibration response,such as the rotation frequencies,multiple frequency components and combined frequencies of the high-pressure rotor and low-pressure rotor.For a wide blade-tip clearance,the blade-casing rubbing may be local rub-impact,where the fault feature frequency is manifested as the pass frequency of the blade and the corresponding doubling frequency,and there are a cluster of side bands on feature frequencies which are modulated by rotating frequencies of the dual rotor.For a small blade-tip clearance,the blade-casing rubbing may be full annular rub-impact,where a strong self-excited vibration is induced by dry friction.The results can provide references to fault diagnosis of blade-casing rubbing and blade-tip clearance design for the dual rotor system of aero-engine.
作者
靳玉林
刘治汶
陈予恕
JIN Yulin;LIU Zhiwen;CHEN Yushu(School of Automation Engineering,University of Electronic Science and Technology of China,Chengdu 611731,China;School of Mechanical Engineering,Southwest Jiaotong University,Chengdu 610031,China;School of Astronautics,Harbin Institute of Technology,Harbin 150001,China)
出处
《航空学报》
EI
CAS
CSCD
北大核心
2022年第12期492-505,共14页
Acta Aeronautica et Astronautica Sinica
基金
国家自然科学基金(52075080,12102084)
航空科学基金(20173319003)。
关键词
航空发动机
双转子系统
叶片-机匣碰摩
有限元法
模态综合法
aero-engine
dual rotor-bearing system
blade-casing rubbing
finite element method
component mode synthesis(CMS)method
