MPTRAC vs SimFlow

MPTRAC is a Lagrangian particle dispersion model for studying atmospheric transport in the free troposphere and stratosphere. It calculates forward and backward air-parcel trajectories from meteorological wind fields, with stochastic diffusion, subgrid wind variation and mixing between parcels. Optional process parameterizations cover convection, sedimentation, decay, gas-phase and aqueous-phase chemistry, and wet and dry deposition. Listed research applications include long-range pollutant transport, volcanic ash dispersion, tracer experiments and atmospheric chemistry.

The browser-based Web Runner can configure, run and visualize simulations, then download results without local installation. It is limited to 10,000 air parcels, 30 days and 10 minutes of model runtime. The model needs meteorological input, normally netCDF files on a regular pressure, longitude and latitude grid. MPTRAC supports hybrid MPI, OpenMP and OpenACC parallelization, and offers visualization interfaces for Gnuplot and ParaView. It is GPL-3.0 software for Linux, self-hosted and web use; listed pricing includes free.

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.