基于欧拉梁单元模型的裂纹转子变刚度特性分析  

Analysis on Stiffness Variation Characteristics of a Cracked Rotor Modelled by Euler Beam Element

作　　者：焦卫东[1,2] 郭红祥[1] 

机构地区：[1]江西理工大学机电工程系,江西赣州341000 [2]嘉兴学院机电工程系,浙江嘉兴314001

出　　处：《机械设计与研究》2013年第2期57-59,68,共4页Machine Design And Research

基　　金：浙江省杰出青年科学基金资助项目(R1100002);浙江省教育厅重点科研计划资助项目(Z201019047)

摘　　要：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 a cracked rotor, its stiffness will change because of the nonlinear opening/closing behavior of the crack. Furthermore, the cracked rotor shows strong nonlinear vibration. In this paper, coupled longitudinal-bending-torsion vibration of the rotor with transverse surface crack is first modeled. Then, comprehensive analysis is made on crack-related stiffness variation characteristics of the cracked rotor.. In the modeling of the cracked rotor, Euler beam element is used. Especially, six degrees of freedom, including axial force, section shear, bending and the torque, are considered. Stiffness matrix of the cracked element is derived by the flexibility coefficients method, and these flexibility coefficients are computed by the strain energy theory. Based on the stiffness computation of the cracked rotor, numerical evaluation is made for some influence factors, such as length of beam element and depth of crack, etc. This study is helpful to understanding and revealing the nonlinear vibration characteristics of the rotor with transverse surface crack.

关 键 词：疲劳裂纹 欧拉梁单元 非线性张合 柔度系数 刚度变化 应变能 

分 类 号：TH113.1[机械工程—机械设计及理论]