Jeffcott转子碰摩故障试验研究

Some Observations of Rub-Impact Fault on Jeffcott Rotor

针对工程实际中遇到的机组转子碰摩故障开展了试验研究。通过大量的试验 ,观测到了工作转速低于一阶临界转速时 ,转定子局部碰摩引起的倍频振动 ;高于一阶临界转速时 ,局部碰摩引起的分频振动以及某些转速段内出现的异频伪共振现象。试验结果与基于碰摩力模型的仿真结果定性一致。试验还表明 ,异频伪共振是高速工作的转子发生碰摩时的主要振动成分 ,这一结论对诊断和抑制高速转子的异常超标振动有积极意义。

In order to observe the nonlinear vibration of rotor when it rubs with stator, a test rig based on Jeffcott rotor model is constructed. Subcritical superharmonic and supercritical subharmonic responses are observed when partial rub-impact occurs. When the subharmonic or superharmonic frequency is near to the natural frequency of the rotor system, a pseudo resonant peak appears at the exact subharmonic or superharmonic frequency on the frequency on the frequency response curve. It is also found that the pseudo resonance is the main component of the lateral vibration when rub-impact fault takes place during high speed operating. The test results coincide well with that of the numerical calculation of analytical model qualitatively.