GMS:MODFLOW Grid Approach
Building a MODFLOW 3D Grid
For models with simple geometry and boundary conditions, the entire model can be constructed using the tools and commands in the 3D Grid module. With this approach, the editing of the MODFLOW data is performed directly on the grid on a cell-by-cell basis. The main steps are as follows:
- Create a 3D cell-centered grid covering the domain to be modeled using the Create Grid command in the Grid menu.
- Use the commands in the MODFLOW menu to initialize and define the data required by the MODFLOW packages.
- Boundary conditions such as wells are defined by selecting the cells and assigning the attributes directly to the cells.
Defining the Layer Data
An important part of a MODFLOW model is the definition of the layer data (hydraulic conductivity, layer elevations, leakance, etc.). While both the Grid and Map module approaches to constructing a MODFLOW model can be used to define the layer data, both approaches may lead to an overly simplistic definition of the stratigraphy. Layers with spatially varying thicknesses can be handled most effectively using a special set of layer data tools provided in GMS. Solids can also be used to define layer data with the Solids→MODFLOW and Solids→HUF commands.
GMS – Groundwater Modeling System
|Modules:||2D Grid • 2D Mesh • 2D Scatter Point • 3D Grid • 3D Mesh • 3D Scatter Point • Boreholes • GIS • Map • Solid • TINs • UGrids|
|Models:||FEFLOW • FEMWATER • MODAEM • MODFLOW • MODPATH • mod-PATH3DU • MT3DMS • MT3D-USGS • PEST • PHT3D • RT3D • SEAM3D • SEAWAT • SEEP2D • T-PROGS • ZONEBUDGET|