Virtual Marine Arsenal

Previously known as OpenFOAM-dev and OpenFOAM-extend, the foam-extend project is a fork of the OpenFOAM open source library for Computational Fluid Dynamics (CFD).

It contains bug fixes and performance improvements, as well as extensions and additional features provided by community contributors such as dynamic mesh and topological change support, turbomachinery extensions including general grid interpolation (GGI), cyclic GGI and mixing plane, block-coupled matrix support, implicitly coupled conjugate heat transfer and other physics coupling, finite area method, comprehensive dynamic mesh (motion and topological changes) capability and GPU support.

A large number of features have been lost within the release of OpenFOAM since version 1.3, the code base has shrunk by more than 40%.

Below is a list of main features of foam-extend which are lacking, lost, deactivated or unusable in ESI releases:

• Turbomachinery features, including General Grid Interface (GGI), partial overlap GGI, cyclic GGI, with improvements in parallel scaling.  First release of a mixing plane stage interface.
• Dynamic mesh with topological changes Sliding interfaces, mesh layering, attach-detach boundaries etc. In foam-extend, full parallel support for topological changes is released for the first time.
• Finite Element Method with support for polyhedral meshes This is mainly used in mesh deformation and over the last 15 years it has proven vastly superior to all other dynamic mesh methods.
• Advanced mesh deformation technology Including tet FEM mesh deformation, Radial Basis Function (RBF) mesh deformation, tetrahedral remeshing dynamic mesh support and solid body motion functions.  All of the above include parallelisation support.
• Library of dynamic meshes with topological changes with full second order FVM discretisation support on moving meshes with topological changes.
• Internal combustion engine-specific dynamic mesh classes such as two-stroke engine and various forms of 4-stroke and multi-valve dynamic mesh classes.
• Finite Area Method providing support for FVM-like discretisation on a curved surface in 3-D, with examples of liquid film modeling.
• Block-coupled matrix support, allowing fully implicit multi-equation solution of NxN equation sets, with full parallelisation support. First release of a block-AMG linear equation solver.
• Fully implicit conjugate-coupled solution framework, allowing implicit solution fo multiple equations over multiple meshes, with parallelism.
• Proper Orthogonal Decomposition data analysis tools, with applications to FOAM field classes.
• Equation reader classes and tutorials.
• Multi-solver solution framework, allowing multiple field models to be solved in a coupled manner.
• A major contribution is solid mechanics modelling, including linear and non-linear materials, contact, self-contact and friction, with updated Lagrangian or absolute Lagrangian formulation.  Solution of damage models and crack propagation in complex materials via topological changes.
• CUDA solver release, provided in full source and as an example of coupling external linear equation solvers with FOAM.
• Library-level support for Immersed Boundary Method and Overset Mesh.
• Major improvements in accuracy and stability of FVM discretisation with options on convection and diffusion discretisation, deferred correction or explicit schemes.
• Algebraic multigrid solver framework.
• 243 tutorials with automated run scripts.
• Automatic test harness.
• Approximately 6.000 bug fixes in fundamental level libraries and discretisation techniques.

OpenFOAM is a registered trademark of ESI Group. foam-extend is a community effort not endorsed by ESI Group.