长外伸段压缩机转子动力学特性研究

Study on Dynamics Characteristics of Long Over-hung Compressor Rotor

为研究长外伸段压缩机转子动力学特性,采用数值分析和实验相结合的方法研究了压缩机转子外伸段长度、莫顿效应以及弹性联轴器质量对转子动力学特性的影响。研究表明:在转子动力学有限元模型中考虑弹性联轴器质量以及增加转子外伸段长度均会降低转子临界转速;莫顿效应引起轴颈处热弯曲产生的热不平衡量和外伸段处的不平衡量共同导致转子外伸段振动大幅增加;适当增加轴承顶隙可有效抑制莫顿效应,从而降低转子进气侧轴振。

In order to study the dynamics characteristics of the long over-hung compressor rotor,the effects of the length of the compressor extension section,the Morton effect and the quality of the flexible coupling on the rotor dynamics were studied by numerical analysis and experiment method.The results show that considering the flexible coupling mass and increasing the length of the rotor extension section,the critical speed of the rotor will be reduced in the finite element model of rotor dynamics;the thermal imbalance caused by the thermal bending at the journal and the unbalance at the extension section of the shaft journal caused by the Morton effect lead to a significant increase in the vibration of the extension section of the rotor;appropriately increasing the bearing backlash can effectively suppress the Morton effect,thereby reducing the shaft vibration on the intake side of the rotor.