基于非线性能量吸收器的裂纹转子延寿研究

项目名称： 基于非线性能量吸收器的裂纹转子延寿研究

项目编号： No.51505099

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 机械、仪表工业

项目作者： 郭超众

作者单位： 哈尔滨工业大学

项目金额： 20万元

中文摘要： 旋转机械是现代社会必不可少的装备，对国民经济的重要行业和国防重点领域有重要的影响。裂纹的出现会缩短转子的使用寿命，通过合理的方法延长裂纹转子的使用寿命，能够充分挖掘转子的使用价值，提高转子系统的可持续利用性，获得巨大的经济效益。本项目将非线性能量吸收器（Nonlinear Energy Sink, NES）引入裂纹转子寿命延长研究中，通过靶向能量传递原理降低转子的振动，从而达到延长转子寿命的目的。首先提出新的呼吸裂纹函数，对裂纹转子系统建模，研究裂纹与振动特性的关系。然后建立裂纹转子-NES系统的动力学方程，研究系统各非线性模态之间的靶向能量传递机理，实现基于NES的裂纹转子振动控制。研究在振动耦合情况下裂纹疲劳扩展，结合断裂力学理论，建立转子振动与疲劳寿命之间的关系，从而提出一种基于NES的裂纹转子寿命延长方法并进行实验验证，为旋转机械转子系统的寿命控制及可持续利用提供重要的技术支持。

中文关键词： 裂纹转子；寿命延长；非线性能量吸收器；靶向能量传递；振动控制

英文摘要： Rotating machinery is indispensable in the modern time which has significant influence on the national economy and key fields of national defense. The existence of cracks in the rotor makes the useful life shorter. Therefore, extension of the rotor life can mine the potential utilization value, which improves the sustainable utilization of the rotor and brings huge economic benefits. This research proposal creatively introduces the nonlinear energy sink (NES) to remaining useful life extension, in which the targeted energy transfer (TET) phenomenon is used to mitigate the vibration amplitude in rotor systems so that the useful life can be extended. First a new function for the breathing crack is developed, and the dynamic equations of the rotor system is modeled and solved to investigate the vibration behaviors. Then the cracked rotor-NES system is modeled and the TET mechanism between the nonlinear normal modes are studied. The parameter optimization of the NES is performed so that the best vibration reduction can be achieved. Moreover, the fatigue crack propagation in combined with the vibration is studied. Based on the fracture mechanics, the relationship between vibration and fatigue life is established. Finally a NES based methodology for life extension for cracked rotor is proposed and an experiment is set up to verify the method. This research will provide important support for the life control and sustainable utilization of the rotor systems in the rotating machinery.

英文关键词： Cracked rotor;Life extension;Nonlinear energy sink;Targeted energy transfer;Vibration control