IGW-Desktop Tutorial 7b - Interactive, hierarchical groundwater modeling

This video demonstrates the use of IGW-Desktop to create a hierarchical groundwater model in a real-time manner. A regional model is created with clusters of multiple pumping wells in the modeling domain. Patches or sub-models are quickly and interactively created around the areas of interest to better resolve the details around the pumping wells. Models at various levels are linked to each other by means of a two-way head coupling mechanism, and the models are solved iteratively until the solution converges. As each patch gets added to the hierarchical tree, the details are visualized in a real-time manner. The steps to create the model are outlined briefly: (1) Create the domain polygon across the entire workspace extent. Assign a hydraulic conductivity in Attributes Explorer • Check ‘Top Elevation’, assign a constant elevation, and check the box next to ‘Random…’, the single-click ‘Random…’ • In the window that appears, change LamdaX and LamdaY to 1000, and click ‘OK’ o Brief explanation here? • Uncheck ‘Use as starting head’ and check the ‘Bottom Elevation/Thickness’ box. Use the default bottom elevation (2) Create a polyline along the left edge of the model, and assign as a constant prescribed head (3) Create a polyline along the right edge of the model, and assign as a lower constant head (4) Discretize the model (5) In Display options, open the Head options window, and check the ‘Zoned (Color Filled)’ box (6) Run the model (7) Add a cluster of well in just above the center of the model domain; add another cluster just to the left of the model domain; (8) Do a “mass edit” on the wells by selecting ‘Wells 2’ from the modeling tree in Attributes Explorer: Change the flow rate to -500 m^3/d, then click ‘Apply this to all sub-node pumping wells’ (9) Discretize and run the model. Note that the flow pattern has significantly changed because of the wells (10) Create a submodel around the 1st cluster of wells, and assign a parent-to-child grid ratio of 4. In the ‘Upscaling/Downscaling’ tab, check ‘Upscaling to parent’ to enable two-way coupling of boundary conditions. (11) Discretize the model. The user can re-size the sub-model display that appears. Refresh the display after re-sizing is finished (12) Run the model, and open the display options. Check ‘Show treemap of model hierarchy’, then click OK. Create a submodel around the 2nd cluster of wells. Note that the tree map window is updated once the 2nd submodel is created. In the ‘Upscaling/Downscaling’ tab, check ‘Upscaling to parent’, then in the ‘Model Grid’ tab, assign a parent-to-child grid ratio of 4 (13) Discretize and run the model (14) Created a patch model within submodel 1-1. Note that the treemap is automatically updated to represent the new hierarchical structure • assign a parent-to-child grid ratio of 3 • In the ‘Upscaling/Downscaling’ tab, check ‘Upscaling to parent’ (15) Click on the discretize icon, and go to the ‘Advanced Discretization Options’ - select ‘Main and all its submodels’ under ‘Selected Model’, then discretize the model (16) Run the model (17) Created a patch model within submodel 1-2. Note that the treemap is automatically updated to represent the new hierarchical structure • check ‘Upscaling to parent’ • Use the default parent-to-child grid ratio of 2 (18) Discretize the model again, and be sure to select ‘Main and all its submodels’ in the advanced options first. Then run the model (19) Draw yet another patch within sub-submodel 1-1-1. Add a 2nd and 3rd patch within sub-sub-model 1-1-1 • assign a parent-to-child grid ratio of 4 • check ‘Upscaling to parent’ (20) Click on the 2nd patch (Model 1-1-1-2) in Attributes Explorer and check ‘Upscaling to Parent’ and assign a parent-to-child grid ratio of 4. Do the same thing for the 1st patch (Model 1-1-1-1) (21) Discretize the model again, and be sure to select ‘Main and all its submodels’ in the advanced options first. Again, note that the treemap has been automatically updated. (22) Run the model, and note the degree of detail captured around each of the wells in the nested models at the “bottom” of the model hierarchy. More details on IGW: please go to https://www.magnet4water.net/GW_home.aspx - Hydrosimulatics Inc. https://www.magnet4water.net