端齿轴段刚度及其对转子动力特性的影响

Stiffness of a Shaft Section with Curvic Couplings and its Effect on Dynamic Characteristic of a Rotor

本文建立了"端齿梁元"的概念,以考虑端齿轴段与整体轴段间的刚度差异.在考虑端齿齿牙间接触传力的情况下进行端齿轴段端面承受单位力(力矩)或单位位移(转角)的三维有限元分析,并由有限元分析结果按梁变形方式整理得出梁元型刚阵中绝对值不同的四组刚度系数的数值,从而得到端齿梁元刚阵.本文还将该端齿梁元应用于有限元子结构模态综合法中,针对一端齿连接转子研究了端齿轴段刚度对该转子动力特性的影响.

The concept of the curvic coupling beam element is presented in this paper,the difference between the stiffness of the shaft section with curvic couplings and that without curvic couplings are considered. At first,it is analyzed by using 3-D finite elemenl method a shaft section with a pair of curvic couplings subjected to a unit force or a unit displacement at one of the end faces of the shaft section. The contact force transmission between the meshed teeth of the curvic couplings is taken into account in the analysis. Then, the values of 4 independent stiffness coefficients of a curvic coupling beam element for the shaft section with curvic couplings can be obtained from the results of the finite element analysis.The presented curvic coupling beam element can be easily incorporated in the finite element—substructure mode synthesis technique for the dynamic characteristic analysis of a rotor. A program called DARC has been developed to analyze the dynamic characteristics for a rotor-bearing-case system with curvic couplings by using the finite element-substructure mode synthesis technique with the curvic coupling beam element.In this paper,a typical rotor-bearing system with two pairs of curvic couplings is analyzed by running program DARC. The natural frequencies and the transient response of the rotor-bearing system are calculated. Two kinds of results with and without considering the effect of the curvic couplings on the dynamic characteristics of the system are given respectively.