【作者】 王彦霖； 杨永锋； 冯海波；

【Author】 WANG Yanlin;YANG Yongfeng;FENG Haibo;Northwestern Polytechnical University,School of Mechanics、Civil Engineering and Architecture;

【机构】 西北工业大学力学与土木建筑学院；

【摘要】 对含有内部裂纹的空心轴转子系统进行动力学建模,研究内部裂纹对转子系统的动力学行为的影响规律。基于空心轴Timoshenko梁-轴模型和中性轴理论,建立以截面惯性矩为变量的裂纹单元刚度矩阵,采用转子动力学有限元方法建立裂纹转子系统的动力学方程。使用谐波平衡法求解动力学方程得到各点的稳态响应,表明裂纹的出现不仅降低了转子系统的临界转速,还使转子在临界转速和亚临界转速附近均出现振动的峰值;分析了裂纹的深度、裂纹的位置对转子系统的影响,表明裂纹位于转轴中部时对转子系统的影响较大,而且随着裂纹的扩展,振动峰值会增大,同时在亚临界转速附近转子系统会发生超谐波共振。研究结论可以为空心轴裂纹的检测和识别提供一定的指导。更多还原

【Abstract】 The modeling of a hollow shaft rotor system with inner cracks and the influence regularity of inner cracks on thedynamic behavior of the rotor system are investigated in this paper. Based on the model of Timoshenko beam and the theoryof the neutral axis, the time-varying area moments of inertia of the cracked section are employed in formulating the periodicstiffness matrix for inner cracks, which is used to formulated the equation of motion by using the finite element method. Byusing the harmonic balance method to solve the equations, the stable response of each node is obtained, which indicates thatthe vibration peaks are present at the first forward and backward critical whirling speeds and the subcritical whirling speedsand critical whirling speeds decrease as a result of the crack. The varying of the critical whirling speed versus differentdepths and different locations of the crack is also analyzed to show that the deeper crack located in the middle of the shafthas a greater influence on the rotor system.The super-harmonic resonances are shown at the subcritical rotating speeds. Theconclusion provide a theoretical guidance for detecting and recognizing the crack faults in the hollow shaft rotor system.更多还原