基于Netgen的层状地质体四面体网格划分方法

为解决三维地质建模中难以表达层状地质体内部属性的问题,将有限元网格划分方法应用于层状地质体建模中,研究基于Netgen进行层状地质体四面体网格划分的方法.以地质钻探数据为数据源,按照钻孔数据分层构建三维表面模型,用三角面片的集合构成封闭的包围壳来描述层状地质体的外部形状;结合Netgen强大的几何自适应和细部划分控制功能,用四面体网格划分方法对形成的三维表面模型进行空间区域划分,从而实现对复杂形状的层状地质体三维模型构建,并分析Netgen的输入、输出数据结构和地质钻探数据到STL格式的三维模型数据、STL格式数据到Netgen网格划分结果数据的生成过程.某矿区多个岩层的模型构建证明该方法稳定、可靠且有效.

Tetrahedral mesh algorithm for stratified geological body based on Netgen

To solve the problem that it is difficult to express the internal properties of stratified geological bodies in 3D geological modeling, a finite element meshing method is applied in the stratified geological body modeling. A tetrahedral meshing method on stratified geological bodies is studied on the basis of Netgen. Taking the geological drilling data as the modeling data source, a 3D surface model of the geological body is constructed according to the drilling data stratification, and the external shape of stratified geological body is described by constituting a closed triangulate surface bounding volume. Combining with the strong geometric self adaption performance and detail subdivision control functions of Netgen, the spatial region division is meshed on the 3D surface model using tetrahedron meshing method, and then the 3D model of complex shape stratified geological body can be built accurately. The input and output data structure of Netgen and the process of transforming from geological drilling data to STL data and from STL data to Netgen meshing data are analyzed. The building of multiple terrane models in a mining area shows that the method is stable, reliable and effective.