主要研究柔性轴-盘转子系统频率突变问题，探究系统参数与频率突变的关联规律。首先以数学方法推导柔性轴-盘转子系统的动力学模型，采用有限元法和假设模态法对系统进行离散化，导出微分方程组，并验证了所建立动力学模型的正确性。为研究固有频率的突变现象，对无量纲参数(转轴半径ri、转盘外半径rD、转盘厚度hD和转盘位置lD)进行参数化分析，发现了柔性轴-盘转子系统的固有频率的等频线现象。在等频线上，零转速条件下的系统固有频率对参数
rD或lD的变化不敏感，基本保持不变。用坎贝尔图和模态图进一步揭示在等频线上的rD和lD的参数变化对柔性轴-盘转子系统振动特性影响的差异。

Here, the frequency mutation problem of flexible shaft-disk rotor system was studied to explore the correlation law between system parameters and frequency mutation. Firstly, the dynamic model of flexible shaft-disk rotor system was derived with the theory of rotor dynamics. The system was discretized with the finite element method and the assumed mode method, and the corresponding differential equations were derived. The correctness of the built dynamic model was verified. Then, to study abrupt change of the system’s natural frequencies, the dimensionless parameters including radius of shaft ri, outer radius of disk rD, thickness of disk hD and position of disk lD were parametrically analyzed, and equifrequency curve phenomenon for natural frequencies of flexible shaft-disc rotor system was found. It was shown that on this equifrequency curve, the system’s natural frequencies under the condition of zero rotating speed are insensitive to change of parameter rD or lD, and basically keep unchanged. Finally, Campbell diagram and modal diagram were used to further reveal the difference of effects of parameters rD and lD changes, respectively on vibration characteristics of flexible shaft-disk rotor system.