Dataset workflow¶
StackNordic provides one route from stored OpenFOAM results to analysis-ready DNS and LES data:
OpenFOAM case
│
├── inspect distribution, decomposition, times and topology
├── decode directly or reconstruct in an isolated workspace
├── derive requested fields with OpenFOAM or a declared numerical provider
├── validate and export canonical snapshots
├── filter or downsample with explicit physical rules
└── publish atomically with provenance and validation results
The dataset manifest records physical time, layout, component order, dtype, coordinates when verified, and provenance metadata.
Reduction rules¶
| Quantity | Reduction declared by the flow or combustion preset |
|---|---|
| Density and pressure | Arithmetic block mean; equivalent to a volume mean on a uniform Cartesian grid |
| Velocity, temperature, progress variable and species mass fraction | Favre mean when density is available |
Volumetric source term such as omega_c_mass |
Volume mean |
Specific source term such as omega_c |
Derive from the filtered volumetric source and filtered density |
| Progress-variable variance | Favre second moment minus the square of the Favre mean |
| SGS stress and kinetic energy | Favre velocity second moments |
Reduction rules are declared through Filtering, Filtering.flow(), or Filtering.combustion(); field names do not select a rule implicitly.
Box reduction trims incomplete blocks at the upper end of each axis. A filtered DNS grid can therefore differ from an independently generated LES grid even when both use the same nominal filter width. Compare physical times and grid axes before computing cell-wise errors. Interpolation aligns coordinates but does not reproduce a conservative volume filter.
Execution¶
Parallel work is bounded by selected work, available CPUs, and estimated memory. Temporary data remains beside its destination and is removed after success or failure.
Operations with progress=True report completed tasks or chunks through Hedgehogs. Failed operations retain the completed count; they do not report full completion.