Aquaveo & Water Resources Engineering News

Did you realize while planning your Groundwater Modeling System (GMS) project that a different unstructured grid (UGrid) would be a better fit? UGrids are very flexible and can be refined around streams, wells, basins, and other objects. But sometimes, one type of UGrid may fit better than another for a particular project. The Voronoi UGrid is one of the more flexible types of UGrids available in GMS. The Voronoi UGrid from UGrid Tool in the Toolbox is there to help convert a UGrid into a Voronoi UGrid.

For most UGrids, the attributes and boundary conditions assigned are associated with the edges, points, and nodes, all on the outer edges of the cells. For a Voronoi UGrid, those things are associated with the point at the center of the cell.

If your model is fairly straight-forward, has structured boundaries or rectangular domains, UGrids with rectangular cells might still be the better choice. Or, if you require computational efficiency, the Voronoi UGrid may not be your best choice. However, if those are not considerations, then using the Voronoi UGrid from UGrid Tool may be a good option for you.

With a Voronoi UGrid, you get even greater flexibility to refine around irregular boundaries thus improving your groundwater model’s accuracy. The cells of the Voronoi UGrid are created with an algorithm that depends solely on the geometry of the points, arcs, and polygons in the active coverage. Voronoi UGrid cells can have more sides (up to eight) than just the three or four sides allowed in most other UGrids. Therefore, it can fit into the boundaries of a model and be refined along arcs and at points much more accurately.

You will find the Voronoi UGrid from UGrid Tool in the Unstructured Grid folder of the Toolbox. The Voronoi UGrid from UGrid Tool only needs the input UGrid and a name for the new Voronoi UGrid it will generate. There are some limitations to the tool. Conversions may not occur if any created final cells would have more than 8 edges. The UGrid being converted must contain only 2D cells. And there can also be no disjoint regions where cells aren’t connected to the rest of the UGrid.

Head on over to GMS to see if the Voronoi UGrid from UGrid tTool will help your model!

Are you wanting to internally couple a CMS-Wave model with your CMS-Flow model? The Surface-water Modeling System (SMS) offers the Inline Steering Model Control option, which allows CMS-Flow steering using CMS-Wave data. The steering is controlled by the CMS-Flow model executable and not SMS. The steering tool is useful in facilitating the process of launching models multiple times. Furthermore, the steering module automates repetitive user tasks. Using the steering tool for CMS will enable data sharing between circulation and wave propagation numerical models.

In SMS version 12.1 and later the Inline Steering option is reached by going to the CMS-Flow Model Control dialog:

1. Build and run a successful CMS-Wave model.
2. Right-click on the CMS-Flow simulation in the Project Explorer and select Model Control.
3. Select the Wave tab and select the Inline steering option under the drop-down in the Wave information heading.
4. Import the specific CMS-Wave solution file.
5. Enter the inline steering value.

Coupling of models is an efficient and accurate means of calculating wave-driven currents, setup and setdown, and wave-current interaction in nearshore regions, including tidal inlets. In SMS version 12.0 and earlier the steering tool can also be used to facilitate the transfer of data from wave models to circulation models and back. In versions 12.1 and later, the CMS-Flow Model Control is used for steering.

When using Inline Steering, it is necessary to build a CMS-Wave model prior to incorporating any data into CMS-Flow. Following that, it is then possible to build a model in CMS-Flow using the stored data and solution files. If you encounter problems with the CMS-Flow simulation results, and notice that neighboring outputs are not quite right, check the Steering Interval option in the CMS-Flow Model Control Dialog. If this option has a number less than 0.25 inputted, it causes problems as there is no proper indication for CMS-Flow to include CMS-Wave solutions in its calculations. To fix this, set the steering interval to a number greater than zero, and the CMS-Flow simulation should respond to the CMS-Wave inputs.

Try Inline Steering for your CMS-Flow models in SMS today!

We are pleased to announce the release of WMS 11.3 in beta! Our developers have been working on several updates to the Watershed Modeling System (WMS). They have added some new features and improved the functionality of others. We'll highlight a few of them here.

GSSHA Permafrost

We are pleased to share that we have now added the ability to model permafrost regions with the GSSHA numeric model in WMS 11.3. With the addition of permafrost options to GSSHA models, your. Permafrost parameters can be defined and set under the GSSHA menus, Job Control and Map Tables. Also when you select a Feature Point/Node and right-click on it and select Attributes to open the Properties dialog. Output graphs and reports on soil temperatures can be generated for further analysis.

Feature Objects Clean Option Updates

We have made several improvements and updates to the Clean Option in our Feature Objects menu. Our developers have improved the cleaning algorithm, so that it is now significantly faster on large coverages. This will improve the efficiency of your model runs.

The Clean Option user interface has also been completely updated. It has the same functionality as the old interface but it now contains more options giving you more flexibility. You can choose to clean all feature objects or only selected ones. You can also now choose to do a full clean on feature objects, or only selected types of clean up.

Search Box for Recent Files

We have also added a search box to the Recent Files dialog. WMS shows the 5 most recent projects you have worked on when you click on File. When you click "More…" below that list of five projects, the dialog that comes up now includes a search box at the top. Rather than scrolling through the list of recent projects, you can now use the search box to find your modeling project more quickly.

These are only some of the great new and updated features in WMS 11.3 beta. Head on over to Aquaveo and try out the WMS 11.3 beta today!

When creating multilayer models, defining layer data can be challenging. This is true for cases involving embedded seams, pinchouts, and truncations. Fortunately, Ground-water Modeling System (GMS) contains a suite of tools for interpolating and manipulating layer elevation data. With the tools in GMS), even complex geologic strata can be modeled quickly and easily. When interpolating layer data for the purpose of defining MODFLOW layer elevation arrays, there are often cases where the interpolated values overlap. In some cases, the best way to fix such a problem is to experiment with the interpolation options or to create some "pseudo-points" to fill in the gaps between sparse scatter points. In other cases, the overlap may correspond to a pinchout or truncation in the layer. In such cases, the elevations need to be adjusted so that there is a small but finite thickness for all cells in the overlapping region.

The first step in fixing layer errors is to use the Model Checker to determine if elevation overlaps occur. If they do occur, the Fix Layer Errors button at the top of the Model Checker dialog can be used to bring up the Fix Layer Errors dialog. Four options are available for fixing layer errors, including Average, Preserve Top, Preserve Bottom, and Truncate to Bedrock. The Average method is useful for modeling the transition zones adjacent to embedded seams. The Preserve Top method can be used to model truncated outcroppings. With the Preserve bottom method, at each cell where an overlap is found the bottom elevation is unchanged and the top elevation is adjusted to top = bot + min thickness. The Truncate to bedrock option differs from the other methods in that it can be used to alter several layers at once.

These are hypothetical scenarios that outline problems and solutions you may encounter when using the Fix Layer Errors Tool in GMS:

You are trying to construct a UGrid model that includes refinement around streams and pumping wells with refinement reserved for the top layers, and inactive cells with a thickness of less than 10 cm.

1. You want a UGrid that includes refinement around streams and pumping wells, yet reserved for the top layers. You get the impression that reserved refinement is achievable only by using the preserve top method.
   It is correct that the preserve top method is a way to apply refinement. The average method does not have any way to refine certain areas, unless the 2D geometry being used as the base already has that refinement. In that case, the refinement would be added to all layers. In other words, refine the 2D grid first, but use the TIN method to create the grid based on that refinement. Use your judgment on if method one works better for your elevation data.
2. You would like all cells with a thickness of less than 10 cm to be inactivated. Yet you find that the only way to inactivate cells less than 10 cm is by using the average method.
   Using the average method and setting the minimum thickness to 0.1m ≠ inactive thin cells. It means cells less than the minimum thickness are not created. Cells are not inactivated until after a MODFLOW simulation has been added. As such, they cannot be inactivated during the creation process. If this is not the result, and there does appear to be thin cells for a TIN grid, further action would be required.

Access the latest version of GMS 10.8 to make use of the Fix Layer Errors tool today!