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Improving a complex finite-difference ground water flow model through the use of an analytic element screening model

R. J. Hunt·Marilyn P. Anderson·V. A. Kelson
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Abstract

This paper demonstrates that analytic element models have potential as powerful screening tools that can facilitate or improve calibration of more complicated finite-difference and finite-element models. We demonstrate how a two-dimensional analytic element model was used to identify errors in a complex three-dimensional finite-difference model caused by incorrect specification of boundary conditions. An improved finite-difference model was developed using boundary conditions developed from a far-field analytic element model. Calibration of a revised finite-difference model was achieved using fewer zones of hydraulic conductivity and lake bed conductance than the original finite-difference model. Calibration statistics were also improved in that simulated base-flows were much closer to measured values. The improved calibration is due mainly to improved specification of the boundary conditions made possible by first solving the far-field problem with an analytic element model.

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R. J. Hunt, Marilyn P. Anderson, V. A. Kelson. 2005-08-04. Improving a complex finite-difference ground water flow model through the use of an analytic element screening model. https://doi.org/10.1111/j.1745-6584.1998.tb02108.x

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