基于2.5维有限元算法的边界处理及网格划分

Analysis of Boundary Treatment and Meshing Method for 2.5D Finite Element Method

摘要:

由于2.5维周期化技术能有效地处理列车振动波传播模拟过程中计算尺度与计算时间的矛盾，因而国内外学者在此理论基础上将FE（有限元）和粘滞边界以及IFE（无限元）等边界处理方法进行耦合.为讨论上述算法中有限元网格划分区域及单元大小对计算精度影响，通过运用软件Matlab编制程序读取Ansys中的模型信息，并将2.5维有限元和无限元边界耦合等算法在其中得以实现.在此基础上发现在相同的网格划分条件下，采用2.5维无限元边界较粘滞阻尼边界具有更高的精度，同时通过选取不同尺寸的有限元模拟区域及最大网格大小，将计算结果与经典解析解进行比较，并对上述网格划分参数的合理选择提出了建议.

Abstract:

As the good performance of the calculation efficiency in the wave propagation simulation, the 2.5D finite element method (FEM) was introduced and coupled with sum of the boundary treatment methods like infinite element method (IFE). In order to analyze the influences of the FEM meshing area and element size to the simulation accuracy. Based on the 2.5D method, the FEM IFE coupled method was fulfilled in Matlab and ANSYS platform. A comparison with the visco boundary treatment show that with the above method results of higher accuracy are ottained than that of the visco boundary. And meanwhile, the reasonable FEM modeling domain and FEM element size are proposed by comparing the simulation results with the classic analytic solution.