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Extending the MODPATH algorithm to rectangular unstructured grids

David W. Pollock
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Abstract

The recent release of MODFLOW-USG, which allows model grids to have irregular, unstructured connections, requires a modification of the particle-tracking algorithm used by MODPATH. This paper describes a modification of the semi-analytical particle-tracking algorithm used by MODPATH that allows it to be extended to rectangular-based unstructured grids by dividing grid cells with multi-cell face connections into sub-cells. The new method will be incorporated in the next version of MODPATH which is currently under development.

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David W. Pollock. 2015-03-05. Extending the MODPATH algorithm to rectangular unstructured grids. https://doi.org/10.1111/gwat.12328

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