| --- |
| license: mit |
| language: |
| - en |
| tags: |
| - physics |
| - computational-fluid-dynamics |
| - navier-stokes |
| - amrex |
| - zarr |
| pretty_name: Native Navier–Stokes simulation voxels |
| --- |
| |
| # Native Navier–Stokes simulation voxels |
|
|
| Lossless exports of velocity and manufactured forcing from Oliver's completed |
| AMReX / incflo experiment. The source has **280 saved states from exact rest |
| through t = 0.995**, including an exactly quiescent interval through t = 0.55. |
| An explicitly labeled prototype may contain fewer states; each release's |
| `manifest.json` is authoritative about its coverage. |
|
|
| ## Layout and access |
|
|
| Each content-addressed `releases/<manifest-hash-prefix>/` directory contains |
| `manifest.json`, `source-best.json`, and `fields.zarr`. The manifest lists actual |
| times, source plotfile names, component order, level geometry, and per-frame, |
| per-level SHA-256 hashes of uncompressed values. Publication never overwrites |
| another release. Pin both the dataset commit and release prefix when citing, |
| downloading, or analyzing the fields. |
|
|
| `fields.zarr/level_0` through `level_4` have axes `(t, x, y, z, component)`. |
| Every level occupies a 64 × 64 × 64 rectangular native patch. Components are |
| `u_x, u_y, u_z, f_x, f_y, f_z`, stored as little-endian float64 in nondimensional |
| model units. Origins are cell-boundary coordinates; cell centers are |
| `origin + (index + 0.5) * spacing`. |
|
|
| The full periodic domain is [−1,1]³. The base spacing is 2/64; four fixed inner |
| cubes have half-widths 0.5, 0.25, 0.125, and 0.0625, with spacing halved at each |
| level. Thus 1024³-equivalent spacing applies **only to the innermost core**. |
| There are 1,310,720 stored cells and 1,179,648 active composite cells per state. |
| Covered coarse cells are retained for fidelity to the native files. Exclude |
| them from composite integrals and select the finest containing cell for slices. |
|
|
| Zarr v3 uses lossless Blosc Zstd/bitshuffle compression, 8³-cell chunks split |
| into velocity and force triplets, and one shard per level per saved state. |
| The entire uncompressed field payload is 16.40625 GiB. No dense 1024³ regridding, |
| float32 conversion, spatial smoothing, or temporal interpolation is performed. |
| Pressure, ghost cells, and solver checkpoints are not included. |
|
|
| Use Zarr 3.3 and `huggingface_hub` / fsspec to open |
| `hf://datasets/ccm/navier-stokes-singularity-simulation@<commit>/releases/<hash>/fields.zarr`. |
| The [interactive Space](https://huggingface.co/spaces/ccm/navier-stokes-singularity-simulation) |
| provides a three-plane viewer without requiring a whole-history download. |
|
|
| ## Validation and limitations |
|
|
| Each exported level is read back and compared exactly with its native float64 |
| values. Checks also require finite fields, exact rest, source timestamps, |
| active-grid peak speed, full-domain volume, and endpoint kinetic energy. |
| Independent C++ slice comparisons test all three axes, and synthetic nested-grid |
| tests check axis order, boundary selection, and refinement precedence. |
|
|
| These are archive and visualization integrity checks, not accuracy bounds. |
| The experiment uses a finite, localized, three-pulse manufactured-force |
| surrogate inspired by the analytical construction. It does not implement that |
| construction's exact infinite hierarchy or certify a Navier–Stokes singularity. |
| The coarser outer grid can remain under-resolved; resampling cannot repair it. |
|
|
| ## Provenance and reuse |
|
|
| Created by Chris McComb's independent numerical project, not affiliated with |
| OpenAI. Run settings, upstream solver revisions, archive hashes, and diagnostics |
| are retained in each release's `source-best.json`. |
|
|
| - [Simulation source](https://github.com/cmccomb/navier-stokes-singularity-simulation) |
| - [Numerical record](https://cmccomb.com/navier-stokes-singularity-simulation/results.html#oliver-complete) |
| - [Method and limitations](https://cmccomb.com/navier-stokes-singularity-simulation/method.html) |
|
|
| Released under the project's MIT license. Cite this dataset's repository, |
| immutable commit, release prefix, and source run ID so the exact fields remain |
| identifiable. |
|
|
| ## Current verified release |
|
|
| 280 states, complete history; t = 0.0 to 0.995. |
|
|
| - Dataset commit: `25266bfc068a729fb169833521eeddfde9c943e9` |
| - Release: `releases/9be10c40938a9d02` |
|
|
