Premium
Simulating MODFLOW‐Based Reactive Transport Under Radially Symmetric Flow Conditions
Author(s) -
Wallis Ilka,
Prommer Henning,
Post Vincent,
Vandenbohede Alexander,
Simmons Craig T.
Publication year - 2012
Publication title -
groundwater
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.84
H-Index - 94
eISSN - 1745-6584
pISSN - 0017-467X
DOI - 10.1111/j.1745-6584.2012.00978.x
Subject(s) - discretization , benchmark (surveying) , advection , multiphysics , flow (mathematics) , mechanics , computer science , modflow , transport phenomena , computational fluid dynamics , mathematical optimization , hydraulics , statistical physics , groundwater flow , physics , finite element method , mathematics , groundwater , geology , geotechnical engineering , thermodynamics , mathematical analysis , geodesy , aquifer
Radially symmetric flow and solute transport around point sources and sinks is an important specialized topic of groundwater hydraulics. Analysis of radial flow fields is routinely used to determine heads and flows in the vicinity of point sources or sinks. Increasingly, studies also consider solute transport, biogeochemical processes, and thermal changes that occur in the vicinity of point sources/sinks. Commonly, the analysis of hydraulic processes involves numerical or (semi‐) analytical modeling methods. For the description of solute transport, analytical solutions are only available for the most basic transport phenomena. Solving advanced transport problems numerically is often associated with a significant computational burden. However, where axis‐symmetry applies, computational cost can be decreased substantially in comparison with full three‐dimensional (3D) solutions. In this study, we explore several techniques of simulating conservative and reactive transport within radial flow fields using MODFLOW as the flow simulator, based on its widespread use and ability to be coupled with multiple solute and reactive transport codes of different complexity. The selected transport simulators are MT3DMS and PHT3D. Computational efficiency and accuracy of the approaches are evaluated through comparisons with full 2D/3D model simulations, analytical solutions, and benchmark problems. We demonstrate that radial transport models are capable of accurately reproducing a wide variety of conservative and reactive transport problems provided that an adequate spatial discretization and advection scheme is selected. For the investigated test problems, the computational load was substantially reduced, with the improvement varying, depending on the complexity of the considered reaction network.