Your first OGS run in 5 minutes

You can run your first OGS simulation in 5 minutes if you start with one of the many existing test cases.
But OGS is a large tool and has much more to offer! It may take some time to master it, but we promise it is worth it.

As a simple example we take the disc with a hole benchmark test case from our benchmark gallery. This benchmark analyzes the stress distribution emerging in a large two-dimensional disc that is stretched in the $y$ direction. The stress distributions (in polar coordinates) obtained in that test case are visualized in the figure below, the instructions to run OGS follow below the figure…

Option 1: Python

If you are familiar with Python and have a working Python installation at hand, the recommended way to use a pre-built OGS is via Python. Otherwise, maybe Option 2 might work for you.

1. Create a Python virtual environment and activate it (for more details see here).
2. Install the python package OGSTools: pip install ogstools. It installs the OpenGeoSys package for you and comes with our collection of Python pre- and post-processing tools and some selected packages that are commonly used together with OGS: PyVista for 3D visualization, Matplotlib, Pandas, and NumPy, among others. After installing OGSTools, you will have a Python environment ready for the whole simulation workflow, from setting up simulation and mesh files to data analysis and creating publication-ready plots.
3. Download the disc with hole example zip file from our GitLab server and unzip it.
   The zip file contains (in the subdirectory Tests/Data/Mechanics/Linear/DiscWithHole) the project file, the simulation mesh, and a file defining the geometries on which boundary conditions are applied. Its contents can be viewed online here.
4. Download the Jupyter notebook underlying the benchmark gallery page of this benchmark case.
   Put the notebook in the same directory as the unzipped project file and mesh from step 3. This directory should contain the following files, now:
   • disc_with_hole.gml
   • disc_with_hole.prj
   • disc_with_hole.vtu
   • Linear_Disc_with_hole.ipynb
   • Linear_Disc_with_hole.py
5. Install JupyterLab to run the notebook later on: pip install jupyterlab.
   Remember: the Python virtual environment from step 1 must still be activated.
6. Open the notebook from step 4 in JupyterLab.
   The notebook already contains plots of the analytical solution to the problem and of OGS simulation results. You can play around with it, now. A good first step is to rerun the entire notebook (Restart Kernel and Run All Cells…, see figure below). This will run OGS – your first OGS run!

Option 2: OGS binaries

That only works on Windows, because we offer prebuilt binaries of OGS for Windows only. Users of Linux or Mac can use Singularity/Apptainer/Docker images of OGS.

1. Download the OGS binaries from our release page.
2. Download the disc with hole example zip file from our GitLab server and unzip it.
   The zip file contains (in the subdirectory Tests/Data/Mechanics/Linear/DiscWithHole) the project file, the simulation mesh, and a file defining the geometries on which boundary conditions are applied. Its contents can be viewed online here.
3. Run OGS:
   
4. View the written output files (*.pvd, *.vtu), e.g., with ParaView.

Next steps

Now that you’ve succeeded with your first OGS run you can dive deeper into OGS and, e.g., adapt the simulation model using our user guide and tutorials.