A handful of ready-to-run cases for you to build upon.

Tutorials are meant as starting points to build your own coupled simulations. Our collection has grown rapidly over the past few years and your contribution is very welcome!

You can find all tutorial case files in the tutorials repository. Get the latest release, or clone the Git repository to easily update them in the future:

git clone --branch=master --depth 1 https://github.com/precice/tutorials.git


## Basic cases

We recommend that you start from one of the following cases, which you can quickly run on your laptop:

## Further cases

In the following cases, you can explore different aspects of preCICE:

## Community projects

Apart from these simple tutorial cases, the community has tried preCICE in different setups. Check out our new community projects section in our forum, or read the community stories.

## General hints

You can start any tutorial by opening multiple terminals, navigating to each participant case, and running ./run.sh. To make the “multiple terminals” part easier, it is often convenient to use a terminal multiplexer, such as Tilix or tmux.

Before running a case again, cleanup previous results with the included cleaning scripts.

### Visualization

When visualizing partitioned simulation results, there are a few hints you may want to consider.

#### Synchronizing results

Most of the solvers support a format that ParaView can read. However, the results may not always be synchronized, as some solvers include timestamps in the file names, while others only include a counter. You may want to use the TemporalShiftScale filter of ParaView to map from a constant time step size to a time.

#### Visualizing OpenFOAM results

To visualize OpenFOAM results, you can either use the bundled OpenFOAM file reader (open the empty .foam or .OpenFOAM file you can find at the case directory), or convert the results to VTK with foamToVTK and load these files in ParaView.

Some versions of OpenFOAM produce additional empty result files when using the preCICE-OpenFOAM adapter, which may lead to a strange “flashing” effect in animations. To work around this, we are deleting such files in the end of each simulation.

#### Visualizing CalculiX results

CalculiX exports results in its own .frd format, which you can visualize in CalculiX CGX (cgx flap.frd). In the CGX window, you can click-and-hold to select different times and fields, or to animate the geometry.

If you prefer to work with VTK files, you can also use tools such as ccx2paraview or a converter included in the calculix-adapter/tools directory. A more complete pre- and post-processing tool for CalculiX is PrePoMax (open-source, only available for Windows).

Are you new to CalculiX? Watch this contributed video tutorial to find out more about pre- and post-processing CalculiX cases for preCICE.

#### Visualizing results of other solvers

• Our FEniCS examples write .pvd files, which you can open in ParaView.
• Our deal.II examples write .vtk files.
• SU2 writes .vtk files.
• code_aster writes .rmed files, which you can open in GMSH. See an example.