《地下水》刊登“一种用于模拟大尺度地下水流动和运移的整合模型”

作者：Junqi Huang, John A. Christ, Mark N. Goltz

刊物:Ground Water，2008年8月18号，第46卷第6期，882-892

关键词：大尺度；地下水流动和运移；网格离散化；计算能力

中文摘要：在对大尺度的地下水污染进行管理时，为了模拟地下水的流动和运移，通常需要对离散域进行细化，例如：（1）在污染源附近区域或者修复技术实施的区域进行地下水流动和运移模拟；（2）对小尺度的非均质性进行说明；（3）表达出地下水-地表水之间的相互作用；（4）上述情况的组合情况。建立在大尺度区域或者网格划分较细的模型需要很大的计算能力。本文建立了与此计算环境相类似的研究域离散-整合模型，该模型可以通过研究域网格细化来有效模拟大尺度地下水流动和运移问题。本方法运用了常用的地下水流动模型（MODFLOW）和污染物运移模型(RT3D)，其可使我们能遇到的几乎所有的地下水流动和运移问题通通得以解决。该方法将一个大的模型研究域分割成若干子域，每个子域上用相同的处理方法进行模型方程求解。在子域边界上应用施瓦茨迭代方法求解水流问题的解。对于污染物运移模型，用一个扩大的数组处理子域边界上的弥散和对流通量。此模型通过常见的单域模型进行证实。模型模拟结果表明，在庞大的计算环境下，本模型相比传统模拟方法来讲，可以节省50%-80%的运算时间，因此可以用于模拟以前难处理的网格离散问题。

An Assembly Model for Simulation of Large-Scale Ground Water Flow and Transport

Auther：Junqi Huang¹, John A. Christ², Mark N. Goltz³

Journal:Ground Water

Key Words:Large Scale；Ground Water Flow and Transport；Grid Discretizations ；Computing Resources

Abstract：When managing large-scale ground water contamination problems, it is often necessary to model flow andtransport using finely discretized domains—for instance (1) to simulate flow and transport near acontaminationsource area or in the area where a remediation technology is being implemented; (2) to account for small-scale heterogeneities;

(3) to represent ground water–surface water interactions; or (4) some combination of these scenarios.A model with a large domain and fine-grid resolution will need extensive computing resources. In this work,a domain decomposition–based assembly model implemented in a parallel computingenvironment is developed,which will allow efficient simulation oflarge-scale ground water flow and transport problems using domain-wide

grid refinement. The method employs common ground water flow (MODFLOW) and transport (RT3D) simulators,enabling the solution of almost all commonly encountered ground water flow and transport problems. The basic

approach partitions a large model domain into any number of subdomains. Parallel processors are used to solve themodel equations within each subdomain. Schwarz iteration is applied to match the flow solution at the subdomainboundaries. For the transport model, an extended numerical array is implemented to permit the exchange of dispersiveand advective flux information across subdomain boundaries. The model is verified using a conventional single-domain model. Model simulations demonstrate that the proposed model operated in a parallel computingenvironment can result in considerable savings in computer run times (between 50% and 80%) compared with conventionalmodeling approaches and may be used to simulate grid discretizations that were formerly intractable.

原文链接：http://onlinelibrary.wiley.com/doi/10.1111/j.1745-6584.2008.00484.x/full