Code Saturne 📖 Wikipedia

code_saturne
Developer	EDF
Initial release	1997; 29 years ago (1997)
Stable release	9.0[1] / June 27, 2025 (2025-06-27)
Preview release	9.0.1[1] / October 17, 2025 (2025-10-17)
Written in	C++, C, Fortran
Operating system	Linux, Unix, macOS
Available in	English
Type	Computational fluid dynamics
License	GNU GPL
Website	code-saturne.org
Repository	github.com/code-saturne/code_saturne

code_saturne is a free and open-source computational fluid dynamics (CFD) solver developed by the research and development division of Électricité de France (EDF). Released under the GNU General Public License since 2007, it is based on a co-located finite volume method and can simulate incompressible or low-Mach number dilatable flows, with or without turbulence and heat transfer.^[1]

The software is integrated into the SALOME platform through the salome_cfd distribution^[2] and can be coupled with the solid thermal code SYRTHES and the structural mechanics code code_aster, both also developed by EDF under free software licences.

Its two-phase extension, Neptune_CFD, co-developed by EDF and the CEA, handles two-phase flows such as water-steam and water-air mixtures.^[3]

Development of code_saturne began in 1997 within EDF's R&D division as an internal tool for nuclear safety studies and thermohydraulics of nuclear power plants.^[3]

In March 2007, EDF released the code under the GNU General Public License, adopting an open development model.^[4] This release encouraged adoption by industrial and academic partners in France and internationally.

The software has since been selected as a benchmark application within the European PRACE (Partnership for Advanced Computing in Europe) project for evaluating supercomputer performance.^[3]

code_saturne solves the Navier–Stokes equations using a co-located finite volume method. It accepts meshes of any type — structured, unstructured, hybrid, conforming or non-conforming — and a variety of cell shapes: tetrahedra, hexahedra, prisms, pyramids, or arbitrary polyhedra.^[1]

Simulated flows can be steady or unsteady, laminar or turbulent, isothermal or non-isothermal, and incompressible or compressible.^[3]

The software provides a wide range of turbulence models covering the following approaches:

• RANS (Reynolds-Averaged Navier–Stokes);
• LES (Large Eddy Simulation);
• hybrid RANS/LES methods (DES, SAS).

In addition to the general-purpose solver, code_saturne includes dedicated modules for specific physics:^[1]

• Combustion: gas flames (diffusion, premixed), pulverised coal combustion with Lagrangian particle tracking, and fire simulation;
• Thermal radiation: radiative transfer in semi-transparent media;
• Atmospheric flows: atmospheric boundary layer, thermal stratification, pollutant dispersion;
• Lagrangian particle tracking: transport of particles, droplets or bubbles in an Eulerian field with two-way coupling;
• Magnetohydrodynamics: coupling of the Navier–Stokes and Maxwell equations;
• Turbomachinery: rotating meshes with sliding mesh interfaces.

The code is parallelised using the Message Passing Interface (MPI) library, enabling it to run on high-performance computing (HPC) architectures.^[3] It can be coupled with the solid thermal code SYRTHES and the structural mechanics code code_aster, notably through the SALOME platform.

code_saturne supports various mesh types, including arbitrary polyhedral and non-structured elements, with non-conforming mesh joining. It does not include a built-in mesher or visualisation module, but is compatible with many standard tools and formats.^[5]

Supported mesh import formats:

Post-processing output formats:

• MED
• CGNS
• EnSight Gold

code_saturne is used in both industrial and academic settings in France and internationally. Approximately 500 engineers and researchers use it within EDF.^[3]

Originally designed for nuclear power plant safety studies, the software is used to analyse flows in primary circuits, cooling systems, coupled fluid-structure heat transfer, and steam generators. It is also employed for modelling wind farms, including turbine wake interactions and layout optimisation.^[3]

The software is used for modelling atmospheric flows, pollutant dispersion, air quality assessment, and wind-structure interactions.^[3]

code_saturne has been used by industrial partners for hydrodynamics applications, notably in the field of naval architecture.^[6]

The software is used in universities and research organisations for developing and validating numerical models, as well as for teaching computational fluid dynamics.

Development is led by the R&D division of EDF. The source code is hosted on GitHub.^[7] Releases follow regular cycles.

A community of users, including engineers and researchers from industry and academia, contributes to the project through the development of physical models, associated tools, and validation cases. An official forum^[8] and technical documentation (user guides, reference manuals, tutorial cases) are available on the project website.

The numerical foundations and validation of code_saturne are described in several peer-reviewed publications:

• Archambeau, F.; Méchitoua, N.; Sakiz, M. (2004). "Code_saturne: A finite volume code for the computation of turbulent incompressible flows – Industrial applications". International Journal on Finite Volumes. 1 (1).
• Fournier, Y.; Bonelle, J.; Moulinec, C.; Shang, Z.; Sunderland, A.G.; Uribe, J.C. (2011). "Optimizing Code_Saturne computations on Petascale systems". Computers & Fluids. 45 (1): 103–108. doi:10.1016/j.compfluid.2011.01.028.

code_saturne runs on Linux and Unix. It is available as pre-compiled packages for distributions such as Debian and Ubuntu, through container images (Docker, Apptainer), or by compiling from source available on the official website.^[9]

Pre-compiled binaries and Singularity (.sif) and Docker container images are also provided by the Open Simulation Center platform,^[10] facilitating deployment on workstations or high-performance computing environments.

On Windows, the software can be used through the Windows Subsystem for Linux.

• code_aster
• SALOME
• Computational fluid dynamics
• OpenFOAM
• Finite volume method

• Official website
• Code_Saturne at EDF
• code_saturne on GitHub