双转子-支承-机匣耦合系统非线性动力学响应分析

Nonlinear dynamic response analysis of dual-rotor-support-casing system

针对航空发动机安全可靠使用的现实问题,对某型航空发动机双转子试验器的转速、转子偏心量以及转速比等方面进行了研究。建立了考虑高低压转子中介轴承的耦合和机匣的弹性变形的简化整机有限元模型,将所建模型与文献中双转子系统算例的数据进行了对比,评价了理论模型的正确性;利用Newmark-β数值积分法求解了系统的非线性动力学响应。研究结果表明:偏心量的位置不同,高压转子与低压转子的振动响应幅值差异明显,当偏心量施加在高压转子部分时,系统的幅值响应更加复杂;转子系统的运动形态受高低压转速比的变化影响显著,系统可能做周期、概周期或者混沌运动。

Aiming at the problem of the aero-engine safe and reliable using, the rotational speed, rotor eccentricity and rotational speed ratio of an aero-engine dual rotor tester were studied. A simplified complete machine finite element model with high and low pressure rotor intermediate bearings and the elastic deformation of the casing was established, the validity of the theoretical model was evaluated by comparing the model with the data of a dual rotor system in the literature, the Newmark-β numerical integration method was used for solving nonlinear dynamic responses of systems. The results indicate that the vibration response amplitude of high pressure rotor and low pressure rotor is distinct difference when the eccentric position is different. The amplitude response is complicated when the eccentricity is applied to the high pressure rotor part. The motion pattern of the rotor system is significantly influenced by the ratio of high and low pressure speed to rotation ratio, the system may do cycle, almost cycle or chaotic motion.