连接件非均匀面压结合部动态性能建模与分析

Modeling and Analysis of Dynamic Performance of Mechanical Joints Under Non-uniform Pressure Distribution

基于栓接结合面非均匀面压分布与分形接触理论,通过静力仿真获得了结合部非均匀面压的分布规律,建立了结合面的动态参数的动力学模型,并将结合面的动态参数换算为虚拟材料的弹性模量、切变模量及泊松比等材料属性参数。提出了考虑结合面非均匀面压影响的栓接结合部有限元模型,结合有限元分析获得栓接结合部的理论模态频率及振型。将理论与实验模态相比较,所提出的模型能够准确地描述机械结合部的固有频率及振型等动态特性,可应用于提高数控机床整机的动态性能建模分析准确性。

Based on the non-uniform pressure distribution and the fractal contact theory,the pattern of non-uniform pressure distribution was obtained through static simulation analysis and a dynamic model of the dynamic parameters of jointed interface was established. By converting the dynamic parameters of jointed interface to the elastic modulus,shear modulus and Poisson＇s ratio of virtual material,the theoretical natural frequency and modal shape were obtained with the use of finite element analysis. Comparing the theoretical modal to experimental modal,the proposed model can accurately describe the natural frequency and modal shape of mechanical joint,therefore it can be applied to improving the accuracy of dynamic performance analysis of machine tool.