The objective of this project is to develop advanced numerical methods for modeling flow and transport processes in coupled surface water/ground water systems. As the relevant processes, and spatial and temporal scales, can strongly differ in the various subdomains of a coupled hydrosystem, different modeling concepts must be chosen for these subdomains. The PIs will investigate appropriate mechanisms for coupling mass, momentum and species transport in ground water and surface water regions. This will include mathematical formulation and algorithmic and software tool development between different domains and models. Efficient discretization techniques, based on finite element technology developed by the PIs and adapted to the dominant processes in each region, will be developed. The stability of these methods will be analyzed, and a priori and a posteriori error estimates will be derived. Time-stepping strategies for accurately handling the different temporal scales within these flow and transport domains will be studied, and fast and robust solution methods for the resulting linear and nonlinear systems of equations will be developed. Representative benchmark problems based on laboratory and field experiments will be formulated and will be used to validate the numerical methods. The resulting methodology will be implemented within a parallel computing framework for distributed and grid computing platforms.
Sustainable management and protection of water resources is one of the key problems of the 21st century. Comprehensive, long-range water resource management requires a careful study of the interaction of ground water and surface water. Historically, ground water aquifers and surface water bodies, such as streams, lakes and wetlands, have been studied in isolation, without properly accounting for the interactions between them. Recent data, however, collected in the United States and abroad, give startling evidence of the effect surface water and ground water systems have on each other. These studies indicate, for example, that water contamination can easily be transmitted from ground to surface water and vice versa. In many cases, the precise location of initial contamination is irrelevant, because the close proximity of ground and surface water can result in both being contaminated. Advanced computer simulators are needed to study and predict the movement of potentially harmful chemical species within these complex environments. In this project, the PIs will develop mathematical models and state-of-the-art computational algorithms and technologies for simulating large-scale ground and surface water systems. The project will involve the collaboration of the PIs with researchers at government laboratories and state agencies, and will include the training of graduate and undergraduate students. The technology to be developed has potential application to other areas, including thermal and chemical processing, biomedicine, and sequestration of carbon dioxide from the atmosphere.
