双盘裂纹转子非线性响应特性

Analysis of Nonlinear Response of Cracked Rotor with Two Discs

研究了轴上含有横向裂纹 ,刚性支承带有居中盘和悬臂盘的双盘裂纹转子的非线性动态响应。考虑轴旋转过程中裂纹的开闭 ,推导出双盘裂纹转子的运动方程。采用仿真计算的方法 ,分析了转速、裂纹深度、外阻尼比的变化对响应的影响 ,并且研究了盘的摆振与横向振动的区别。结果表明 ,裂纹转子随转速变化 ,响应会出现丰富的非线性特征 ;裂纹深度的增大 ,会导致系统响应出现分叉与混沌 ;外阻尼可以有效抑制非线性响应 ;盘的摆振对于裂纹的出现 ,较之横向振动 ,包含有明显的高次谐波分量 。

This paper investigates the nonlinear response of cracked rotor with midspan and overhung disc. Considering the breathing of crack in rotation, the motion equations are derived for the eight degrees of freedom's system. The equations are solved with 5 step Runge Kutta method. The simulation results show that system parameters, such as rotating speed, crack depth and external damping have large influence on the nonlinear response. With the variation of rotating speed, bifurcation and chaos will happen in response. In the process of quasi period to chaos, it can be observed clearly the phenomenon of torus bending and twisting, which finally will lead to chaos. With the increase of crack, there will occur quasi periodic and chaotic response. The increase of external damping will suppress non synchronous response and fix response to periodic motion.