March 20, 2026 Software Open Access

Multiphase Python Repository by HZDR

Schlegel, Fabian; Fombonne, Clement; Hänsch, Susann; Krull, Benjamin; Lehnigk, Ronald; Meller, Richard

The multiphasepy is a Python toolkit for building, running, and maintaining CFD simulation case collections for the software released by the OpenFOAM Foundation (but also others, like Ansys Fluent or Siemens Simcenter Star-CCM). It combines reusable library modules with practical command-line tools to cover the full simulation lifecycle: case templating, batch execution, monitoring, post-processing, validation support, repository comparison, and publication workflows.

At its core, multiphasepy helps teams move from individual case setups to scalable, structured projects containing a large collection of setups, e.g. a validation database. Cases can be provided as templates that are parameterized at runtime, metadata can be managed in a machine-readable way and cases can be conveniently batch-processed with the workflow management tool Snakemake both on workstations and Slurm-based HPC systems. Using a container-based software environment (e.g. Apptainer or Docker) the case collection becomes fully portable. An integrated Copier template allows the creation and maintenance of multiple independent case collections.

Beyond execution, the package supports quality assurance and communication of results: tools are included for automated checks, fuzzy-logic based evaluation, data conversion, visualization, and generation of artifacts suitable for reporting and dissemination. This makes multiphasepy a practical bridge between day-to-day CFD case work and long-term, reproducible research software operations in collaborative environments.

Command-Line Tools

The multiphasepy package provides a comprehensive suite of command-line tools for CFD workflow management, data processing, and quality assurance. All tools follow the naming convention mpy<function> and provide --help for detailed usage information.

Workflow Management

• mpycopy : Copy and render templated cases
• mpydocker : Launch customizable Docker development environments
• mpywatch : Progress display and real-time data visualization
• mpyworkflow : Create and manage cases projects allowing batch processing

Data Processing

• mpyconv : Convert data files between formats
• mpypost : Mathematical post-processing operations
• mpyvisualize : Visualize simulation result files

Quality Assurance

• mpytest : Run CFD code functionality tests
• mpyfuzzy : Evaluate simulation goodness using fuzzy logic
• mpyhooks : Run git hooks for code quality checks

Utilities

• mpyidentify : Identify file types and associate tags
• mpyrpcmp : Compare two repositories (file-based)
• mpyrpdiff : Compare repositories using git diff
• mpyshrun : Wrap shell commands with logging

Publishing

• mpypublish : Publish software to Rodare repository

Installation

The multiphasepy package requires Python 3.12 or newer.

Install the latest release from Gitlab PyPI:

python -m pip install multiphasepy --extra-index-url https://codebase.helmholtz.cloud/api/v4/projects/8786/packages/pypi/simple 

For full environment setup and platform-specific notes, see the installation guide in the documentation.

Acknowledgements

OpenFOAM® is a registered trade mark of OpenCFD Limited, producer and distributor of the OpenFOAM® software via <www.openfoam.com>. The Multiphase Python Repository by HZDR is not compatible with the software released by OpenCFD Limited, but is developed for the software released by the OpenFOAM Foundation via <www.openfoam.org>.