GMS:HydroGeoSphere

HydroGeoSphere (HGS) is a three-dimensional control-volume finite element simulator created by Aquanty. HGS can be used to model the entire terrestrial portion of the hydrologic cycle. It uses a globally-implicit approach to simultaneously solve the 2D diffusive-wave equation for overland/surface water flow and the 3D form of Richards’ equation for variably saturated groundwater flow.

Graphical Interface

The GMS interface for HydroGeoSphere contains multiple components. These components include:

• An unstructured grid (UGrid)
• HydroGeoSphere coverages
• HydroGeoSphere simulation, including the Simulation Control

Building a HydroGeoSphere Simulation

Example of a MODFLOW 6 simulation in the Project Explorer

Before building a HydroGeoSphere (HGS) simulation, a 3D UGrid of the project area is required. While the project can contain multiple UGrids, only one UGrid can be attached to each HGS simulation.

To create a MODFLOW simulation:

1. Right-click on an empty space in the Project Explorer, or right-click on " Project" in the Project Explorer, and select New Simulation | HydroGeoSphere.

When the simulation has been initially created, the selected UGrid will be linked to the simulation and the simulation packages will appear in the Project Explorer.

HGS Simulation Right-Click Menus

In the Project Explorer, right-clicking on a HGS simulation brings up a menu with several commands. Some of these commands are common to other Project Explorer In the Project Explorer, right-clicking on HGS simulation brings up a menu with several commands. Some of these commands are common to other Project Explorer right-click menus. Others are unique to the simulation right-click menus. Some of these unique commands are:

• " Simulation Data"
  • Simulation Run Queue – Opens the Simulation Run Queue dialog which shows all current simulation runs.
• " HydroGeoSphere Simulations"
  • New Simulation – Creates a new MODFLOW 6 simulation in the Project Explorer. This simulation will not contain any of the packages in any existing simulations and therefor the packages must be added. Also, creating a new simulation using this method requires linking a UGrid to the simulation.
  • Save Multiple Simulations – Saves all HGS simulations in the project and exports all files needed for the model run.
• Model
  • Simulation Control – Opens the Simulation Control dialog where the HGS simulation parameters are set.
  • Materials – Opens the HGS Materials dialog.
  • Export – Saves out the simulation files.
  • Run grok – Opens the Run grok.exe dialog where GMS will generate the GROK file. The GROK file contains all of the information and instructions required for the HGS simulation.
  • Run phgs – Opens the Run phgs.exe dialog where the HGS simulation will run.
  • Run hsplot – Opens the Run hsplot.exe dialog which will post-process the simulation results for viewing.
  • Solution Plots – Opens the Solution Plots dialog which will display plots generated from the HGS solution.
  • Save Simulation – Saves the simulation and exports all files needed for the model run.
  • Save Project and Simulation – Saves the simulation and exports all files needed for the model run.
  • Read Solution – Loads the solution file for the associated simulation. Requires that the simulation has had a successful run.

Modeling Notes

• GMS allows multiple HGS simulations to exist in a single GMS project.

HGS Files

Running HGS requires multiple executable files. These include:

• grok.exe – A pre-processor that uses the Grok input file containing the information and instructions for the HGS simulation.
• phgs.exe – Performs the model simulation.
• hsplot.exe – A post-processor that generates the simulations results.

External Links

• HydroGeoSphere website
• HydroGeoSphere Theory
• HydroGeoSphere Reference Manual