OpenSim vs SimFlow

OpenSim models and simulates how humans, animals, robots, and their environment move and interact. Its graphical interface displays models and supports creating and analyzing simulations. Models can contain rigid bodies, joints, constraints, contact, muscles, and other actuators. Movement analysis tools include inverse kinematics, inverse dynamics, static optimization, and forward dynamics; Computed Muscle Control can generate muscle-driven forward simulations. The API is usable through Matlab, Python, Java, and C++, and GUI scripting uses an embedded Jython shell. Plugins can add analyses and model components, but must be built for the same OpenSim version and platform. The graphical interface is distributed for 64-bit Windows and Mac, while there is no public Linux GUI distribution; the API source can be built for Linux. OpenSim is free and open source under Apache 2.0, though models, examples, and plugins may have separate licenses. It is intended for research and teaching and welcomes academic and commercial applications. Documentation, tutorials, and a discussion forum are available. Downloading requires a SimTK account.

SimFlow is desktop software for computational fluid dynamics, covering the workflow from mesh generation through post-processing. Simulations stay on the user's hardware, and the software runs on Windows, Linux, and macOS, including Apple Silicon. Jobs can run on a local cluster, remote server, or cloud, with HPC-grade parallel computing and no per-core or hourly charges. The full simulation engine is included in every plan. CAD imports include STL, STEP, IGES, OBJ, and BRep; results can be exported in VTK, Fluent, Tecplot, and Ensight formats. SimFlow integrates with ParaView, OpenFOAM, Docker, and Windows Subsystem for Linux. The free plan has no signup, credit-card requirement, or time limit, but is limited to 200,000 mesh nodes and one CPU. Professional costs €8,000 per year; Enterprise costs €10,000 per year. Commercial plans include a 30-day trial. Perpetual licenses are also available, with one year of maintenance and optional yearly renewals.