Unsaturated Flow Modeling—Exact Solution to Approximate Problem?
Publication: Journal of Water Resources Planning and Management
Volume 120, Issue 2
Abstract
Unsaturated flow models are increasingly being used in ground‐water quantity/quality studies to predict recharges due to rainfall. This paper presents a critical examination of the current practice of using numerical models in light of the approximate nature of problem identification. Three issues are addressed: (1) Sophistication of models; (2) specification of boundary conditions; and (3) selection of hydrogeological properties. To systematically study these issues, two ground‐water models are used, a simple lumped parameter model and the numerical model, UNSAT1. The models are applied to two hypothetical unsaturated domains as well as to a field site where extensive monitoring of ground‐water conditions is reported in literature. The results indicate that, in the case of spatially homogeneous soil profiles, errors in recharge predictions due to improper problem identification are more significant than those due to model simplification. The study exemplifies the importance of problem identification in modeling studies.
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Information & Authors
Information
Published In
Journal of Water Resources Planning and Management
Volume 120 • Issue 2 • March 1994
Pages: 186 - 198
Copyright
Copyright © 1994 American Society of Civil Engineers.
History
Received: Aug 31, 1993
Published online: Mar 1, 1994
Published in print: Mar 1994
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