转子系统不对中-碰摩耦合故障的动力学特性

针对由于轴承不对中而引起不对中-碰摩耦合故障的转子-轴承系统，建立了双盘不对中-碰摩耦合故障转子系统力学模型和有限元模型.基于非线性有限元方法，使用等效不对中力矩及接触理论研究了不同转速对系统动力学特性的影响.研究结果表明，不对中-碰摩耦合故障常常以碰摩故障特征为主，并且二倍频出现较早及其峰值会急速增大.进一步运用小波基函数对故障信号进行等宽频带的划分，通过对故障转子系统频域响应中二倍频峰值变化趋势的分析研究发现，可将二倍频比例值作为含有不对中故障转子系统故障严重程度的一个判断依据.

Dynamic Characteristics of Misalignment-Rubbing Coupling Fault for Rotor System

For the misalignment-rubbing coupling fault rotor-bearing system caused by misaligned bearing, mechanical and finite element models of dual-disk misalignment-rubbing coupling fault rotor-bearing system were established. The equivalent misalignment moment and contact theory were used to study the effect of rotational speed on the dynamics characteristics with the nonlinear finite element method. The results showed that the misalignment-rubbing coupling fault mainly embodied in the rubbing fault, and the frequency-doubled appeared early with the peak increased rapidly. The fault signal was further divided to same width parts with the wavelet basis function, and the change trend of the double frequency peak showed that the double frequency ratio value is a judgment basis for the fault degree of the rotor system containing misalignment fault.