带套齿连接结构的转子系统振动稳定性实验研究

In order to study the vibration stability of the rotor system with spline connection structure, the internal friction force expression of the spline connection structure was derived and the vibration instability conditions of the rotor system were solved. The experimental rotor system with two different spline connections including rigidity and flexibility spline was designed and built. The vibration stability of rotor system with different spline connection structure was studied experimentally. It was found in the experiment that the vibration instability of the rotor system with flexible spline connection structure was easy to occur due to internal friction between the tooth surfaces of the inner and outer. Characteristic of instability was appearing prominent sub-harmonic components in rotor vibration and the sub-harmonic frequency was the first natural frequency of the rotor system. The threshold speed for the occurrence of sub-harmonics was slightly higher than the first critical speed of the rotor system. The increase of misalignment had a stimulating effect on sub-harmonics and promoted rotor instability aggravated and increased tightening torque of the lock nut had an inhibitory effect on instability. The rotor system with rigid spline connection structure had crossed the third critical speed in the working speed range and there was no instability phenomenon. The "resonance" experiment was carried out for 300s in the first mode and the second mode respectively, there was no sub-harmonic vibration component during the experiment and the rotor remained stable. The results show that the stability of the rotor with rigid spline connection structure is higher than that of a rotor with flexible spline connection structure.