基于微观接触模型的支撑基座刚度分析

Support Base Stiffness Analysis Based on Microscopic Contact Model

针对支撑基座的竖直刚度计算问题,围绕如何提高有限元计算准确性,提出一种等效刚度模型替代宏观结构模型的分析方式,基于有限元法进行微观粗糙表面仿真和分析,利用积分思想计算等效刚度。通过轮廓扫描仪获取真实工件表面的形貌数据,重构符合高斯分布的微观粗糙表面,使用ANSYS软件仿真计算接触刚度,结果与不同理论接触模型对比,验证了有限元微观接触表面刚度的合理性。将宏观结构模型有限元计算刚度与等效刚度模型计算刚度对比,结果表明接触面的塑性变形和曲面的基体变形对刚度影响最大,为后续支撑系统的结构优化提供依据。

Aiming at the problem of vertical stiffness calculation of support base,and focusing on how to improve the accuracy of finite element calculation,this paper proposes an analysis method in which the equivalent stiffness model replaces the macro structure model.Based on the finite element method,the micro rough surface simulation and analysis are carried out,and the equivalent stiffness is calculated using the integration idea.The topography data of the real workpiece surface is obtained through the contour scanner,and the micro rough surface conforming to the Gaussian distribution is reconstructed.The contact stiffness is simulated by using ANSYS software.The results are compared with different theoretical contact models,and the rationality of the finite element micro contact surface stiffness is verified.Comparing the calculated stiffness of the macro structure model with that of the equivalent stiffness model,the results show that the plastic deformation of the contact surface and the matrix deformation of the curved surface have the greatest impact on the stiffness,which provides a basis for the subsequent structural optimization of the support system.