OpenFOAM vs PySDM
OpenFOAM
openfoam.comPySDM
open-atmos.github.ioSide by side
| Figure | OpenFOAM | PySDM |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Windows | Yes | — |
| macOS | Yes | — |
| Linux | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 1 | 1 |
| Spec score · Physics Simulation Software | 8.7 (#5) | 8.1 (#28) |
| Data export | Yes | Yes |
| Delivery mode | desktop | hybrid |
| Free plan | Yes | Yes |
| Intended users | OpenCFD describes its services for science and engineering companies, consultancies, and universities. | The package is intended as a building block for simulation systems involving dispersed phases, with development focused on atmospheric cloud physics applications. |
| License | OpenFOAM is distributed under the GNU General Public Licence (GPL). | PySDM and PySDM-examples are free/libre open-source software released under the GNU GPL v3 license. |
| Purpose | OpenFOAM is an open-source computational fluid dynamics toolbox for simulating fluid flow, heat transfer, and related physical processes. | PySDM simulates particle populations undergoing diffusional and collisional growth and breakage, with a focus on atmospheric cloud physics and aerosol, cloud, and rain microphysics. |
| Support | OpenCFD offers a one-year support package covering installation, bug fixes, updates, CFD assistance, and code customisation, with a maximum number of service hours per year. | The project recommends GitHub Discussions for help understanding, using, and extending PySDM, and its GitHub issue tracker for reporting incorrect or undocumented behavior. |
Plans
In their own words
OpenFOAM
OpenFOAM is a free, open-source computational fluid dynamics toolbox for simulating fluid flow, heat transfer, and related physical processes. It provides pre-processing, mesh generation, solvers for different flow and physics problems, and post-processing tools. Built-in utilities include blockMesh and snappyHexMesh, and it can convert meshes from external formats. ParaView visualization is supported through the paraFoam launcher, reader modules, VTK conversion, and VTK output during simulations. OpenFOAM runs on Linux, macOS, and Windows, and supports self-hosted use. Its current release is v2606, released on 26 June 2026; GPU offloading is available as a compile-time option, with that work on a separate development track. It is distributed under the GNU General Public Licence. OpenCFD offers a one-year support package for installation, fixes, updates, CFD assistance, and code customization, subject to a yearly service-hours maximum. It does not respond to support queries without a prior package. Training courses are also offered, with prices provided through a schedule or enquiry process.