Frequently Asked Questions

ESI Group just announced the acquisition of OpenCFD Ltd, the leader in Open Source Computational Fluid Dynamics (CFD) software. ESI Group becomes the owner of the OpenFOAM®  trademark, which is widely recognized and used in many industries, notably in automotive, energy, and aerospace as well as academic.

What is OpenFOAM?

OpenFOAM (Open Source Field Operation And Manipulation) is a free, open source software package for CFD produced by OpenCFD Ltd. and distributed by the OpenFOAM Foundation. It has a large user base across most areas of engineering and science, from both commercial and academic organizations. OpenFOAM has an extensive range of features to solve anything from complex fluid flows involving chemical reactions, turbulence and heat transfer, to solid dynamics and electro-magnetics.

Why has ESI acquired OpenCFD?

The virtual engineering market continues to show an increase in the demand for open source software, specifically in CFD domain where the need for large scale parallel computing continues to increase. ESI Group already has OpenFOAM expertise via its earlier acquisition of Mindware Engineering, which will be a natural complement to the OpenCFD team and ensure a successful downstream integration. ESI believes in the openness of OpenFOAM and sees it as a key component of its strategy in providing users with an end to end virtual prototyping solution. ESI Group will be investing in OpenFOAM to scale it to reach more users and make it an integral part of its product portfolio.

What will happen to the existing ESI CFD software (ACE+ Suite)?

The OpenFOAM market and ACE+ market are complementary. The ACE+ Suite has a very large user community in a very unique multi-physics domain. ESI will continue to develop ACE+ Suite of the products and will grow and support this user community.

How do I get professional support to use OpenFOAM?

ESI-OpenCFD provides a range of support services to OpenFOAM users including:

• scheduled and on-site training courses at a range of locations worldwide;
• a support package including CFD assistance and code customization for OpenFOAM;
• contracted code development projects for OpenFOAM;
• large enterprise subscription including software support, platform services (tuning, benchmarking, porting), collaborative functionality integration and strategic planning;
• CFD consultancy and system integration.

Why should I choose ESI-OpenCFD to support me with OpenFOAM?

OpenCFD are the producers of OpenFOAM. The benefits of receiving support from producers of the software are:

• CFD assistance and support is backed up by years of experience in CFD with OpenFOAM;
• developments are made by people with a proven background in programming OpenFOAM, in line with the entire development of OpenFOAM, for inclusion in the OpenFOAM distribution;
• training is conducted by people who really know OpenFOAM and who regularly teach OpenFOAM on-site to customers and within our busy schedule of hosted courses;
• system integration can include changes to the OpenFOAM distribution itself, rather than introducing additional processes that are clumsy and create a maintenance burden.

ESI, as an established enterprise software vendor, will further strengthen quality assurance and support to ensure a viable, trusted, and scalable solution for both large enterprises as well as SMEs (small to medium enterprise). Furthermore, ESI has a global team dedicated to providing support and services around OpenFOAM. This team has extensive experience in all aspects of OpenFOAM from installation to customization to engineering support and services.

Why should I consider OpenFOAM?

The open source nature of the software provides these benefits:

• full control and flexibility over the software;
• rapid implementation of new technology;
• substantial cost savings for large (parallel) simulations;
• peace of mind due to access to source code, specifically for certain enterprises including government agencies;
• flexibility in allocating CFD budgets according to business priorities.

What is the license for OpenFOAM?

OpenFOAM is distributed under the GNU General Public Licence (GPL), the most widely used free software license. There are two main elements to the GPL, designed to prevent open source software being exploited by their inclusion within non-free, closed sourced software products:

• software that includes source code licensed under the GPL inherits the GPL license;
• if compiled binaries of software licensed under GPL are distributed, the source code must also be made available by the distributor.

These aspects of the license discourage exploitation, because if a closed sourced software product that includes open source software is sold for a fee, anyone purchasing the product could demand the source code and redistribute it for free. Apart from this, the license is designed to offer freedom, in particular it does not force users of the software to make modifications or developments publicly available.

What are the capabilities provided by OpenFOAM?

The OpenFOAM software consists of the following components.

• CFD solvers for a variety of flows including: incompressible, multiphase, heat transfer, natural convection, combustion, compressible (high speed), electro-magnetics, discrete particle.
• A suite of physical modeling libraries for turbulent simulation (Reynolds-averaged, large-eddy, detached-eddy, etc), transport and rheology, thermo-physics (gas, solid and liquid), reaction kinetics and chemistry, pyrolysis, thin films, particle tracking, and more.
• Mesh tools including: mesh generation for complex (CAD) geometries, using snappyHexMesh, and simple geometries using blockMesh; mesh conversion from a wide range of common commercial formats; and other tools to manipulate meshes, e.g. defining patches on the mesh boundary, checking mesh quality, resizing meshes, etc.
• Post-processing capability including: visualization using ParaView (also open source); run-time post-processing including automatic generation of visualization files (cutting planes, iso-surfaces, streamlines, etc); data manipulation tools; converters to third-party formats for visualization.
• Core technology that includes: finite volume numerics on arbitrary unstructured polyhedral meshes; linear matrix solvers, and ordinary differential equation solvers; low-level parallelization that ensures almost everything, from meshing, pre-processing, through simulation, to post-processing, runs in parallel; dynamic mesh capability including arbitrary mesh interface (AMI, aka GGI), solid body motion, internal mesh motion, dynamic refinement and un-refinement.

How can I obtain OpenFOAM?

You can download OpenFOAM from the OpenFOAM Foundation website at http://www.openfoam.org/download

What do I need to do to get it running on my computer?

OpenFOAM is distributed for Linux operating systems. The source code can be compiled directly on any Linux system, but there are also source/binary packs available specifically for Ubuntu, SuSE and Fedora distributions. The open source license gives user freedom to install OpenFOAM on hardware and platforms of their choice. For example, it can be installed within a virtual machine on a Windows machine or on a public or private cloud computing service.

What guarantee do I have that OpenFOAM will be always be free and open source?

The OpenFOAM software is copyright to the OpenFOAM Foundation, a non-profit, non-stock corporation which was established to distribute OpenFOAM exclusively under a no-cost open source license to the general public. The Bylaws of the Foundation ensure that OpenFOAM will only be distributed free and open source.

How can I customize OpenFOAM?

Since OpenFOAM is released under the GPL, you can customize OpenFOAM as required. You can change existing code or add new code to the OpenFOAM source code and build your own binaries. You just need to ensure that you comply with the GPL if you decide to redistribute OpenFOAM whether in modified form or not.

How often is OpenFOAM updated? How many releases per year?

OpenCFD continuously develops major new functionality and feeds those developments into each new major release of OpenFOAM, at least once a year. Through the website bug reporting system users submit bugs and feature enhancements for OpenFOAM. These fixes and any enhancements are fed into the OpenFOAM code base and, following a period with few reported bugs, a minor (stable) version of the software is released.

When was OpenFOAM developed?

Henry Weller began writing the OpenFOAM software, originally named FOAM, in 1989, following the creation of the C++ programming language. As Chief Scientist, Henry will continue to develop OpenFOAM at ESI-OpenCFD.

Who is in charge of developing OpenFOAM?

OpenCFD develops and maintains the OpenFOAM software and releases it through the OpenFOAM Foundation. Through the Foundation’s bug reporting system, users can contribute changes to OpenFOAM, such as bug fixes and minor feature additions. The Foundation is also planning a contributions repository to allow larger contributions to be made available for download. Over time, prioritized contributions may be integrated by OpenCFD into the OpenFOAM distribution.