挠性转子系统碰摩故障传播特性的实验研究

研究了柔性联接的双跨度挠性转子发生碰摩时系统的响应征兆;将振动信号的快速付立叶变换(FFT)幅值谱阵列和轴心轨迹设置为特征参量,对不同截面和2个相互垂直方位的碰摩特征进行了对比.结果表明:碰摩故障在转子间具有传播能力,靠近碰摩部位的响应强度最大;碰摩的典型特征表现为FFT谱中1X分量幅值增大,并出现2X、3X、4X谐波分量;轴心轨迹形状显示出碰摩作用点的截面方位信息;最典型征兆表现为碰摩响应的1X分量所对应的频率坐标降低,其降低幅度与碰摩的程度相关.

Experimental Study of the Propagation Characteristics of Rub-Impact Faults on a Flexible Rotor-Bearing System

The rub-impact response features of a flexible rotor with two spans and four fixed mass disks were investigated. Thus the rub-impact behaviors of the system at different conditions and different locations were examined and compared with that at the optimized steady state (corresponding to a rotary speed of 4 000 r/min), using FFT spectra and center orbits of the responses as the characteristic parameters to express the vibration features. It was found that the sensors mounted nearest to the rub-impact location were able to pick up the violent responses, in this case the faults were dominated by the harmonious increase of the component 1X (X referred to the rotor's rotating frequency) and by the synchronous emergence of 2X, 3X, and 4X emerge on the FFT spectra, and the magnitudes of the components 1X, 2X, 3X, and 4X corresponded to the rotating frequency of the rotor. The shapes of the rotor's center orbits reflected the phase information of the faults. Moreover, the rub moment created by the contact between the dynamic rotor and static shell made the rotating frequency drop, owing to the damping action, and the magnitudes for the rotating frequency to decrease were related to the rub-impact severity.