斜裂纹转子刚度特性分析

在材料力学和断裂力学的基础上,运用应变能释放率的方法,得出斜裂纹的刚度矩阵.讨论在裂纹全开的状态时,裂纹倾角、轴细长比和裂纹深度对转轴刚度的影响,并对裂纹处于旋转时的开闭情况及相应轴的刚度变化规律进行研究.结果表明:当裂纹处于全开状态时,随着裂纹倾角的增大,裂纹的刚度随之减小,轴刚度的变化随着裂纹深度的增大更加显著;当裂纹处于开闭状态时,随着裂纹深度的增加,轴的刚度不再一直减小,而是有一定规律的波动,即时变特性,此时,轴的耦合振动随之增强,转子的动力特性变得愈加复杂.

Stiffness Characteristics Analysis of a Rotor With Slant Crack

The stiffness matrix of the slant crack was obtained based on material mechanics and fracture mechanics theory through the use of strain energy release rate method. While the crack is fully open, the influence of the crack angle, the axial slenderness ratio and the crack depth on the stiffness of the shaft was discussed. At the same time, the opening and closing conditions in the rotating state and the stiffness change law of the corresponding shaft were studied. The results show that, when the crack is in the fully open state, the stiffness of the crack decreases with the increase of the crack angle. And the shaft stiffness changes more significantly with the increase of the crack depth; when the crack is in the opening and closing state, with the increase of the crack depth, the shaft stiffness is no longer decreases, but there is a certain law of fluctuation, which is time-varying characteristics, in this case, the shaft coupling vibration also increases, the dynamic characteristics of the rotor becomes increasingly complex.