OpenFOAM

OpenFOAM is a free, open-source computational fluid dynamics toolbox for simulating fluid flow, heat transfer, and related physical processes. It includes tools for preparing simulations, generating meshes, solving multiple flow and physics problems, and processing results. Mesh utilities include blockMesh and snappyHexMesh, and the software can convert meshes from several external formats. For visualization, it connects with ParaView through its paraFoam launcher, reader modules, VTK conversion, and VTK output during simulations. OpenFOAM runs on Linux, macOS, and Windows, and supports self-hosted use. It is distributed under the GNU General Public Licence. The current release is v2606, released on 26 June 2026; it introduces GPU offloading as a compile-time option, though GPU work remains on a separate development track. OpenCFD offers a one-year support package covering installation, bug fixes, updates, CFD assistance, and code customisation, with a yearly service-hours limit. Support queries are not answered without a prior package. Training is also offered, with course pricing provided through a schedule or enquiry process.

OpenFOAM combines simulation, mesh, and post-processing tools in a free GPL-licensed package. Support and code customisation are separate services, and support is subject to a yearly hours limit.

OpenFOAM is suited to science and engineering companies, consultancies, and universities that need fluid dynamics simulation tools. It may also suit teams that can work with a GPL-licensed toolbox and arrange separate support if needed.

OpenFOAM is a configurable computational fluid dynamics toolbox for simulating fluid flow, heat transfer and related physical processes. It fits engineering and science teams, consultancies and universities that can manage a flexible simulation workflow. Its free GPL licence and broad toolset are the main draw; obtaining help or custom code requires a separate service package.

Overview

OpenFOAM covers the CFD workflow from pre-processing and mesh generation through solving and post-processing. Solvers support multiple flow and physics types, while mesh utilities can build new meshes or convert several external formats. This breadth is valuable for organizations with varied cases and in-house expertise, but it is less suitable for readers seeking a tightly packaged application with support included.

The software is distributed under the GNU General Public Licence. OpenFOAM v2606, released on 26 June 2026, adds GPU offloading as a compile-time option. GPU work remains on a separate development track, so this release is better viewed as an incremental option for teams willing to compile and evaluate that path than as a mature, general-purpose GPU solution.

Key features

Meshing and simulation

Built-in blockMesh and snappyHexMesh provide two distinct approaches to mesh creation, and external mesh conversion broadens the ways a project can start. The combination of meshing tools and many solver types lets experienced users shape a workflow around the problem rather than fit the problem to one preset model. That control is an advantage for specialist teams, while the need to choose and configure components makes it a demanding choice for occasional users.

Visualisation and output

OpenFOAM connects with ParaView through the paraFoam launcher, reader modules, VTK conversion and VTK output during simulations. This gives teams a defined route from computed results to 3D visual inspection. Data export is supported, which helps when results must move into other analysis or reporting workflows.

Security and operations

Documentation disables user-supplied system calls unless allowSystemOperations is enabled and warns that enabling them creates a security risk. Administrators should therefore treat system-call permissions as an operational decision rather than a convenience setting.

Pricing

The software itself has no charge and no free trial is offered because the plan is already free. Support and code customisation are separate services. OpenCFD's support package runs for one year and covers installation, bug fixes, updates, CFD assistance and code customisation, subject to a maximum number of service hours during that year. OpenCFD says it does not respond to support queries without a prior support package, so teams requiring a response channel must budget for that service. Foundation, Advanced, application-focused and virtual training are offered separately, with pricing handled through the training schedule or an enquiry.

Platforms

OpenFOAM is delivered as desktop software for Linux, macOS and Windows, and can also be self-hosted. That range supports mixed operating-system environments and organizations that prefer to control deployment, while self-hosting places installation and administration responsibility with the user.

Who it's for

OpenFOAM is aimed at science and engineering companies, consultancies and universities. It is a strong fit when users need several physics options, custom meshing, external mesh import and direct control over the simulation workflow. It is a weaker fit for learners or departments that want a guided interface, bundled support or a ready-made model library, since the product is a configurable toolbox and assistance requires a paid package.

Pros and cons

Pros

• Free GPL licence: removes software fees and permits an open-source deployment model.
• End-to-end CFD coverage: meshing, solvers and post-processing sit in one toolbox, reducing the need to assemble unrelated core components.
• Flexible mesh handling: blockMesh, snappyHexMesh and external-format conversion accommodate different starting points.
• ParaView integration: paraFoam, reader modules and VTK paths provide established routes to 3D result visualisation.

Cons

• Support is not included: OpenCFD requires a prior yearly support package before answering support queries, and service hours are capped.
• GPU capability is still developing: v2606 makes offloading a compile-time option, but the work remains on a separate development track.
• Operational expertise is necessary: teams must handle configuration, deployment and security decisions such as enabling system calls.

Alternatives

For a broader directory of options, see Physics Simulation Software.

• Open Source Physics is a free option spanning Android, iOS, Linux, macOS, web and Windows, making it preferable when cross-platform educational access matters more than OpenFOAM's specialist CFD toolbox.
• Physics Classroom Physics Interactives is free on Android, iOS and the web, a better choice for browser-based interactive learning.
• Algodoo uses a freemium model on iOS, macOS and Windows and focuses on 2D scene creation and physics-based construction.
• OpenSim is free and open source for Linux, macOS, Windows and API use, with downloads requiring a SimTK account.
• Xcos is free on Linux, macOS and Windows and is distributed with Scilab.
• GNU FisicaLab is GPL software for Linux and Windows.
• SimFlow offers a free tier and free trial on Linux, macOS, web and Windows.
• FeenoX is free GPLv3+ software for Linux, web, API and self-hosting, without a graphical interface.

Verdict

Choose OpenFOAM if your engineering or science group needs a no-cost, extensible CFD foundation with serious meshing, solver and ParaView pathways. Its main reason to look elsewhere is the support model: organizations that need included assistance, a guided application or a mature GPU workflow should choose a more packaged alternative.