中文摘要：

根据转子动力学理论，建立了具有质量突变特性的非线性转子系统力学模型及动力学方程。利用数值方法分析了频率、突变质量比及非线性刚度在质量突变后对轴心位移的影响，定义了质量突变后的暂态过程时间并确定了碰摩参数区域。结论表明，质量突增对刚性及柔性转子系统的轴心位移均具有较大影响，同时质量突减亦会增大柔性转子系统的轴心位移，暂态过程时间与系统阻尼、质量突变时的轴心位置及系统工作频率有关，碰摩参数区域随着质量突增幅度及质量偏心距的增大而增大等。

英文摘要：

Dynamic model and equation of a nonlinear rotor system with sudden change mass were established based on rotor dynamics. Using numerical integration method, the influence of working frequency, sudden mass ratio and nonlinear stiffness on axis displacement was studied. Transient time after the mass suddenly changed was defined and the rubbing parameter region was determined. The conclusion indicates that sudden increased mass has huge influence on the axis displacement of both flex rotor and rigid rotor, sudden decreased mass can enhance axis displacement of flex rotor system, too; transient time is related with system damp, axis azimuth when mass suddenly changed and operating frequency; rubbing parameters region will increase with sudden change mass amplitude and mass eccentricity enhancing, and etc.