OVERVIEW AND APPLICATIONS OF THE ANALYTIC ELEMENT METHOD

The objectives of this presentation are two-fold: to present a brief overview of the analytic element method along with the principles it is based upon, and to present several applications to field problems.

The Analytic Element Method is a computational method based upon the superposition of analytic expressions; it is approximate and can be applied, in principle, to represent any three-dimensional or two-dimensional vector field.

The Analytic Element Method is applicable to both finite and infinite domains, and is typically applied to problems that contain internal boundaries. The method was first developed in the early seventies in order to solve a groundwater flow problem: the modeling of the effect of the Tennessee-Tombigbee Waterway on the surrounding aquifers, where the groundwater model needed to simulate flow both on a regional scale (about 50 by 80 miles initially) while simultaneously simulating the effect of some 60 wells in a 3000 feet long test section of the excavation. The nature of the method, superposition of analytic expressions, makes it possible to deal with very large models, while still maintaining a high degree of accuracy on a small scale.

Three applications of the Analytic Element Method will be discussed briefly:1) the Twin Cities Metropolitan Area Groundwater Model, 2) a large-scale analytic element model of the Yucca Mountain area in Nevada, and 3) the Dutch National Groundwater Model, NAGROM. Emphasis will be placed on how the analytic element approach differs in these applications from finite difference models, and on how these models have been, and are being, used to answer practical questions.

The remainder of the presentation will focus on recent developments of the method, and how these may affect the construction of regional groundwater models using the Analytic Element Method in the future.