岩土工程亿级单元有限元模型可扩展并行计算  

Scalable parallel computation for finite element model with hundreds of millions of elements in geotechnical engineering

作　　者：张友良[1] 谭飞[1] 张礼仁[1] 施明明[1] 

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071

出　　处：《岩土力学》2016年第11期3309-3316,共8页Rock and Soil Mechanics

基　　金：国家重点基础研究发展计划(973计划)(No.2014CB047100);国家自然科学基金(No.11272330);中科院"十二五"信息化专项(No.XXH12503-02-02-11)~~

摘　　要：讨论了亿万单元有限元模型的可扩展并行计算方法。从软件和硬件两个方面提出了前处理、并行计算方法、程序算法、后处理实现等核心问题的解决方案。采用网格加密方法生成一亿单元的有限元模型,利用对偶原始有限元撕裂内联法(FETI-DP)求解系统方程。基于图论理论建立了子区域间的通讯拓扑关系,实现了子区域间点对点通讯,避免速度慢、通信量大的全局通讯。在自主开发程序基础上,增加相应模块,采用面向对象编程技术和MPI消息传递库开发程序。对一个一亿多单元的工程实例运用5000核并行计算,得到了超线性加速比。计算结果在专用图形工作站上进行后处理,显示和交互操作速度良好。研究在两方面实现了突破:一是将模型规模提高到了一亿多单元;二是同时调用了5000个计算核来并行运算,并得到了很高效率。高分辨率有限元并行模拟研究成果可为岩土工程中结构特别复杂、计算区域特别大、地质情况复杂等模拟提供很好的技术方法和实现手段。The scalable parallel computation of finite element models with hundreds of millions of elements is discussed. The software and hardware solutions for the preprocessing, parallel computing method, software algorithms, and postprocessing are proposed. A finite element model of one hundred million elements is generated by grid encryption method. And the dual-primal finite element tearing and interconnecting method（FETI-DP） is utilized to solve the finite element system of equations. The topological connections among sub-domains are set up based on graph theories. Point to point communications are built to accelerate data exchange among sub-domains and to avoid the time-consuming global communications. Some modules are written based on an in-house code using object-oriented programming technique and message passing interface（MPI）. A numerical example with more than one hundred million number of elements is carried out using 5000 cores at the same time; and super-linear speedup is obtained. The postprocessing is performed on a graphical workstation; and the interactive operations respond quickly. The study shows two big improvements： one is that the numerical model has more than one hundred million numbers of elements; the second is that 5 000 cores are used at the same time and high efficiency is obtained. The research results show that the high resolution numerical simulations provide an efficient tool for large size and complex geological conditions simulations in geotechnical engineering.

关 键 词：并行有限元 可扩展并行计算 岩土工程 对偶原始有限元撕裂内联法(FETI-DP) 

分 类 号：O242.21[理学—计算数学]