项目名称: 复杂接触表面问题有限元计算及微观结构分析
项目编号: No.11271247
项目类型: 面上项目
立项/批准年度: 2013
项目学科: 数理科学和化学
项目作者: 侯磊
作者单位: 上海大学
项目金额: 60万元
中文摘要: 碰撞、弹塑变形问题等交通运输器安全试验目前通常采用实验室实物模型与计 算机模型相结合。对三维复杂区域的接触,滑动控制目前国际标准模拟方法采用接触算法。我们在本课题中采用流固耦合非牛顿流体方程初边值问题求解三维层结构特性。通过基于变分原理的摄动问题有限元方法,在高性能软件的平台上实现不确定数据的挖掘处理。由Sobolev空间嵌入原理将模型按接触区域进行分层单元剖分,将复杂区域剖分为若干相互连接、不重叠的六面体与空间平面四边形单元。同时建立随机接触问题微观变量与宏观有限元计算模型进行超收敛计算与模拟仿真对比,得到模型的能量与速度等一系列参数的变化曲线。 另外,接触表面间断问题又可采用渐近摄动方法的边界层理论进行研究。由此得到的微分方程特征函数既可作为优化有限元基函数的解又可建立一种新型的非线性特征值的渐近方法,这是估计材料特定参数的方法之一。然后使用人工边界条件特征谱处理方法估计间断定解条件。
中文关键词: 接触表面;自适应有限元;应力分布;奇异摄动;
英文摘要: The safety test of transportation device, including impact test and elastic-plastic deformation, is now simulated both in laboratory and computer. Contact deformation algorithm is an international standard method to simulate the slip control on complex 3-D surface. In this project, coupled non-Newtonian visco-elastic equations with initial boundary value are used to solve the 3-D layer structure. A finite element method (FEM) based on variational principle is used to solve the perturbation problem. The related data-mining of the uncertainties is processed by high performance software. According to the embedding principle, a stratified element division of the model is processed, and the complex boundary will then be divided into several mutual connected yet not overlapped 3-D hexahedron and 2-D rectangular elements. Micro variables of stochastic contact problem and macro-scale FEM models are established, on which super-convergent calculation and simulation is processed. Varying curves of parameters, including energy and velocity, can then be obtained. On the other hand, the boundary layer theory of asymptotic perturbation method is also a way to study the discontinuous contact surface. The characteristic function space gained can be used both to optimize the primary function of FEM, and to establish a new asympt
英文关键词: contact interface;adaptive FEA;strain distribution;singular perturbation;