The OpenFOAM Foundation is pleased to announce the release of version 13 of the OpenFOAM open source CFD toolbox. Version 13 includes: a rewrite of mesh zones which can dynamically update and are easier to use and more robust (replacing the lousy topoSet): field-based Lagrangian, a 65% complete, more flexible, extensible and efficient replacement to the existing code; improvements to MULES to guarantee boundedness and accelerate solutions, e.g. in multiphase flows; a rewrite of mass transfer modelling; better visualisation with ParaView working on decomposed cases, foamVTKSeries for animations and improved foamMonitor; several improvements and additions for multi-region simulations, case configuration, meshing, function objects, multiphase flows and combustion.

OpenFOAM 13 includes the following highlights.

• Modular Solvers: include deactivating flow, thermophysics and models switches.
• MULES: guarantees boundedness irrespective of iterator convergence.
• Multiphase: significantly accelerated simulations with the multiphaseEuler solver.
• Transport/Thermo: rewritten mass transfer modelling for the multiphaseEuler solver.
• Combustion: improved ignition and flame model for simulation of engines.
• Particles: 65% complete field-based Lagrangian is more flexible, extensible, efficient, …
• Meshes: upgraded mesh generation and coupling of multiple mesh regions.
• Mesh Zones: robust, usable, flexible, and more functional replacement.
• Multi-region Simulation: improved NCC and mesh stitching and mapping.
• Function Objects: improved scalarTransport, add power, reaction rate, cutLayerAverage.
• Models: added propellerDisk models and improved fvFieldSource.
• Boundary Conditions: improved pressure, temperature and mass diffusion conditions.
• Case Configuration: new foamMergeCase tool .
• Visualisation: ParaView can read decomposed cases, foamVTKSeries for animations.
• Cases: new examples for single phase, multiphase, incompressible and compressible flows.
• Other: The foamNewApp script can create starter code for a non-CFD application.