不同深度呼吸型斜裂纹转子的非线性输出频率响应特性分析

Analysis of nonlinear output frequency response characteristics of breathing slant crack rotor with different depth

将具有呼吸型斜裂纹的转轴作为研究对象,结合非线性输出频率响应函数(NOFRF)理论对转轴上的斜裂纹故障进行识别。根据非线性输出频率响应函数理论及辨识算法求出系统不同阶次的NOFRF值,并对斜裂纹转子在不同裂纹深度时的NOFRF值进行分析。实验结果表明,随着裂纹深度的增加,系统的非线性特性会随之变强,根据系统的NOFRF值对裂纹的不同深度比较敏感这一特征,从而实现对转轴上的斜裂纹故障进行准确的诊断。

The breathing slant crack rotor is used as the research object,the nonlinear output frequency response function method is introduced to fault diagnose of rotor system with breathing slant crack.The NOFRF values of different order of the system can be obtained according to the theory of nonlinear output frequency response function and the identification algorithm.The NOFRF values of the slant crack rotor at different depth are analyzed.The experimental results show that the nonlinear characteristics of the system will become enhancement with the decrease of the crack depth.The sensitivity of NOFRF value to different crack depth can be used to effectively monitor the slant crack fault in the rotor system.