航空发动机转子紧固结合面微动-摩擦耦合作用机理及其响应演变研究

Aiming at the problems of contact fatigue and restraint failure of the fastening interface of aero-engine rotor under centrifugal and other loads, the fretting-friction coupling mechanism of the interface and system response are studied. The rotor components are taken as the research object, and the combination of theoretical analysis and experimental test is adopted. From the perspective of microscopic contact mechanism to macroscopic dynamic response analysis, two key scientific issues are focused on: fretting-friction coupling mechanism of the bolted joint surface and evolution law of nonlinear response of the discontinuous rotor system. Based on the fractal contact theory and the statistical contact theory of n-point asperities, and considering the external excitation, a stacked multi-scale fretting contact model of the joint surface is established. The nonlinear dynamic characteristics of the fretting interface are studied, and the fretting-friction interaction of the interface under external load excitation is explored. A representation method of discontinuous structure in rotor system dynamics model is proposed, and the nonlinear response of the rotor system combined with the surface contact effect is analyzed. The correspondence between the mechanical regulation of the joint surface and the evolution of the rotor system response is explored. It is expected that the fretting-friction coupling mechanism of the bolted joint surface of rotor components will be revealed, and the dynamic response prediction and control method of the discontinuous rotor system will be obtained. The research can provide theoretical basis for improving the connection performance of rotor components and improving the steady-state response of the system.

针对航空发动机转子紧固结合面在离心等载荷作用下易产生接触疲劳和约束失效等问题，开展连接界面微动摩擦耦合机理和系统响应研究。项目以转子部件为研究对象，采用理论分析和试验测试相结合的方法，从微观接触机理到宏观动态响应分析角度，围绕紧固结合面的微动-摩擦耦合作用机理和非连续结构转子系统非线性响应演变规律两个关键科学问题进行研究。以分形接触理论和n点微凸体统计接触理论相结合并考虑外激励，建立结合面的堆叠多尺度微动接触模型，分析微动结合面的非线性动力学特性，探究外载荷激励下的结合面微动-摩擦相互作用。提出非连续结构在转子系统动力学模型中表征方法，分析综合结合面非线性接触效应的转子系统非线性响应，探究结合面力学调控与系统响应演变间的对应关系。预期揭示转子部件紧固结合面的微动摩擦耦合机理，获取非连续结构转子系统动态响应预测和调控方法。研究可为转子部件连接性能提高及改善系统稳态响应提供理论依据。

本项目依据研究目标和研究内容，进行了详细的研究，实现了项目计划书的要求，取得了一定的成果。项目主要取得的成果：(1)采用逆向三维建模技术重构了多尺度粗糙表面形貌，完成了接触面接触特性分析；研究了不同表面形貌与接触界面加、卸载力的相互作用规律；(2)揭示了表面形貌APSD能量的分布特性、表面加工质量与不同频率分量能量分布的关系、表面圆谱的变化关系；(3)完成了连接界面的接触刚度、接触阻尼模型建立；(4)基于有限元分析软件，并考虑连接界面的非线性摩擦特性，获取了不同预紧力下的转子螺栓连接界面接触应力分布；提出了由激励部件、界面路径和受体部件组成的振动传递系统模型，分析了频域内的力传递特性；(5)研究了转子系统在偏心力、滚动轴承非线性接触力、重力场和机动载荷作用下的非线性响应演变规律。通过本项目在国际老牌力学、动力学及ASME汇刊等，发表SCI学术论文11篇，EI论文1篇。SCI中JCR 2区及以上6篇，Top期刊3篇。国家发明专利4个。培养在读硕士研究生10名。依托本项目获得省自然科学学术成果奖二等奖1个（排名1），省教学成果奖二等奖1个（排名3），省级等各层次人才称号3个，其它获奖及荣誉6个。