论文部分内容阅读
裂纹转子旋转过程中,由于裂纹的非线性开/合行为导致转子刚度的变化,进而导致转子复杂的非线性振动。文章研究存在横向表面裂纹转子的纵-弯-扭耦合振动建模,并对裂纹引发的转子变刚度特性进行综合分析。转子建模采用欧拉梁单元模型,并考虑了轴向力、截面剪力、弯矩以及扭矩作用下转子运动的六个方向的自由度。裂纹单元的刚度矩阵采用柔度系数法导出,而柔度系数则由应变能理论求得。在此基础上,对一些影响裂纹转子刚度变化的主要因素如裂纹深度,梁单元长度等进行了数值分析。所得研究结果,有助于理解和揭示具有横向表面裂纹转子的非线性振动响应特性。
During the rotation of the cracked rotor, the rotor stiffness changes due to the nonlinear open / close behavior of the crack, which leads to the complicated nonlinear vibration of the rotor. In this paper, the longitudinal-torsional-torsional coupled vibration modeling of transverse surface cracked rotor is presented, and the comprehensive analysis of rotor-induced variable stiffness is carried out. The rotor model uses the Eulerian beam element model and takes into account the freedom of the six directions of rotor movement under axial force, section shear force, bending moment and torque. The stiffness matrix of the cracked element is derived by the law of compliance, while the compliance factor is derived from the strain energy theory. On this basis, some of the main factors that affect the stiffness change of cracked rotor, such as crack depth and beam element length, were numerically analyzed. The results obtained will help to understand and reveal the nonlinear vibration response characteristics of a rotor with transverse surface cracks.