含碰摩故障的转子-盘片-机匣系统动力学特性分析

以转子-盘片-机匣耦合系统为研究对象,基于ANSYS有限元软件建立有限元模型,通过实验测试得到的固有频率验证了模型的有效性;采用点点接触来模拟叶片和机匣之间的碰摩故障,并通过测试的响应数据,进一步验证了所采用模型的正确性和可行性.最后,仿真分析了定转速情况下不同侵入量、定侵入量和定间隙下不同转速对系统动力学响应的影响.研究结果表明:叶尖碰摩主要激发高倍频成分,且在系统俯仰刚体模态频率附近会出现倍频幅值放大现象;定侵入量条件下,高转速碰摩情况时系统的频率成分减少,系统的法向碰摩力也随着转速的增大而变化;定间隙条件下,在高转速碰摩情况时倍频幅值会超过转频,在一次连续碰摩过程中会出现多次碰撞反弹现象. 

Dynamic characteristic analysis of rotor-blade-casing system with rub-impact fault

Taking a rotor-blade-casing coupling system as the research object, finite element model of the rotor-blade-casing coupling system was established by ANSYS software, and then the validity of the model was verified by the natural frequencies obtained from experimental measurement. A point-point contact element was used to simulate the fixed-position rubbing fault between the blade and the casing, and further the validity and feasibility of the method adopted were also verified by the testing response data. Finally, the influences of different penetrations at a certain rotate speed, the constant penetration at different rotate speeds and the constant clearance at different rotate speeds on system vibration responses were analyzed. The results show that rubbing on the tip of blade mainly excites high multiple frequency components, and the amplitude of the multiple frequencies near the pitching rigid model increases. Under the constant penetration at different rotating speeds, the frequency components of the system is reduced at high speed rubbing conditions, and the normal rubbing force also changes with the increase of rotating speed. Under the constant clearance at different rotating speeds, the amplitudes of some multiple-frequency components are greater than those of rotating frequency when the rubbing appears at high speed, and repeatedly collision rebound can be observed during continuous rubbing.