转轴上裂纹在通过临界转速过程中的呼吸特征

为了研究复杂涡动引起的裂纹非线性呼吸行为对转子临界转速的影响,在恒速裂纹转子运动方程的基础上构建带横向裂纹Jeffcott转子的通用运动方程,对裂纹转子加速通过临界转速的过程进行了数值研究。结果表明:不平衡量方位角对临界转速有较大影响;在临界转速附近,裂纹的呼吸减弱;在恒加速过程中裂纹转子的最大响应滞后于重心转向。在转子实验台上进行裂纹转子通过临界转速的实验验证,观察数据支持理论研究结果。

Breathing Characteristics of the Crack in a Rotating Shaft when Rotor Passing through Critical Speed

Based on the dynamic equations of cracked rotor under constant speed, the general dynamic equations of a Jeffcott rotor with a transverse crack are developed for studying the influence of nonlinear breathing behavior of the crack due to whirling on the critical speed of the rotor. The vibration response of the cracked rotor, when the rotor is accelerating and passing through critical speed, is investigated by numerical method. The results reveal that the imbalance orientation angle has a greater influence on the critical speed, the crack breathing behavior is weakened near the critical speed, and the maximum response of the cracked rotor during constant accelerating process is fall behind the rotation of the center of gravity. The experiment of passing through critical speed of a cracked rotor was made on a rotor testing platform. And the experimental observations support the analytical results.