# OpenLB - Open Source Lattice Boltzmann Code

The OpenLB project is a C++ package for the implementation of lattice Boltzmann
methods addressing a vast range of transport problems.

## Documentation

A comprehensive user guide is available at [0].

Papers featuring OpenLB are collected at [1].

Up-to-date Doxygen documentation can be generated via `make doxygen`
or accessed at [2].

[0]: https://www.openlb.net/user-guide/
[1]: https://www.openlb.net/articles/
[2]: https://www.openlb.net/DoxyGen/html/index.html

## Dependencies

The only mandatory external dependency of OpenLB is GNU Make and a C++ compiler
with C++14 support. This includes all reasonably recent versions of GCC, Clang
and ICC.

ParaView and gnuplot are optional dependencies for visualizing simulation results.

## Build

1. Adjust the `config.mk` file to fit your local compiler environment.
   Preset values are for GCC compilation without parallelization support.
2. Build the library core using `make`

### Examples

All examples may be compiled in one go using `make samples`.

To compile an individual example such as a basic flow around a cylinder:

1. Switch to `examples/laminar/cylinder2d`
2. Execute `make`
3. Run the program via `./cylinder2d`
4. Follow the program output while it is running
5. VTK and gnuplot results can be found in the `tmp/` folder

## Community

The OpenLB forum [3] is an open discussion board for all aspects of LBM and OpenLB.
Feel free to post any problems, questions, suggestions or contributions.

You can also reach us via mail at [email protected]

There is a yearly one-week Spring School [4] where you can learn about LBM and
OpenLB directly from the developer team and invited guest lecturers.

A list of all present and past contributors is available at [5].

[3]: https://www.openlb.net/forum/
[4]: https://www.openlb.net/spring-school-2021/
[5]: https://www.openlb.net/authors/

## How to cite OpenLB

```
@article{OpenLB2020,
  title = {OpenLB - Open Source Lattice Boltzmann Code},
  year = {2020},
  issn = {08981221},
  doi = {10.1016/j.camwa.2020.04.033},
  journal = {Computers \& Mathematics with Applications},
  author = {Krause, Mathias J. and Kummerl{\"a}nder, Adrian and Avis, Samuel J. and Kusumaatmaja, Halim and Dapelo, Davide and Klemens, Fabian and Gaedtke, Maximilian and Hafen, Nicolas and Mink, Albert and Trunk, Robin and Marquardt, Jan E. and Maier, Marie-Luise and Haussmann, Marc and Simonis, Stephan},
}
```

This article is available as open access [6].

[6]: https://doi.org/10.1016/j.camwa.2020.04.033

## License

OpenLB is provided as open source under the terms of the GNU GPL v2 license.

See `LICENSE` for details.