中文摘要：

针对汽轮机组、航空发动机等两跨三支撑轴系常发生不平衡振动故障问题，研究了各转子不平衡对轴系振动特性的影响．首先建立两跨三支撑轴系动力学有限元模型，在各跨转子上分别施加同相和反相不平衡激励，对轴系不平衡稳态响应进行分析，并搭建了轴系模拟实验台．结果表明：这种轴系转子跨内加重振动以单转子不平衡振动特性为主，转子间振动相互影响较大，具有明显的悬臂转子外伸端振动特性．

英文摘要：

To solve the problem of frequent unbalance vibration existing in two-span three-support shafting of steam turbine units and aircraft engines, the effects of rotor unbalance on the shafting vibration were studied. The specific way is to set up a finite element model for the two-span three-support shafting, then to apply in-phase and out-phase unbalance excitations to each rotor, and finally to perform a steady-state response analysis for the shafting. Meanwhile, a simulation test rig was also established. Results show that the vibration characteristics of the shafting caused by weighing in outside span is mainly of the single rotor type, and the vibration influences each other among rotors significantly, with vibration characteris- tics of the overhung rotor kind.