Improved water table dynamics in MODFLOW.

Tom Clemo

doi:10.1111/j.1745-6584.2005.0021.x

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Improved water table dynamics in MODFLOW.

Tom Clemo

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Abstract

The standard formulation of a block-centered finite-difference model, such as MODFLOW, uses the center of the cell as the location of a cell node. Simulations of a dynamic water table can be improved if the node of a cell containing the water table is located at the water table rather than at the center of the cell. The LPF package of MOD-FLOW-2000 was changed to position a cell's node at the water table in convertible cells with a water table. Improved accuracy in the upper regions of an unconfined aquifer is demonstrated for pumping from a partially penetrating well. The change introduces a nonlinearity into the solution of the flow equations that results in slightly slower convergence of the flow solution, 7% slower in the presented demonstration. Accuracy of simulations is improved where vertical flow is dominated by a moving water table, but not when a large water table gradient dominates over the water table movement.

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Geological Phenomena Geology Models, Theoretical Sensitivity and Specificity Soil Water Movements Water Supply Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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Tom Clemo. Improved water table dynamics in MODFLOW.. https://doi.org/10.1111/j.1745-6584.2005.0021.x

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