|
|
| # HDF5 schema |
|
|
| Each `data/<split>/<case_id>.h5` file is a self-contained trajectory. `N` |
| varies by trajectory; `T=601` throughout. |
|
|
| | Dataset | Shape | Dtype | Meaning | |
| | --- | --- | --- | --- | |
| | `uvp` | `[T, N, 3]` | `float32` | Channels `[u, v, p]` | |
| | `time` | `[T]` | `float64` | Dimensionless public time, `0:0.1:60` | |
| | `points` | `[N, 2]` | `float32` | Graph-node coordinates | |
| | `cells` | `[F, 3]` | `int32` | Triangular connectivity | |
| | `boundary` | `[N]` | `uint8` | `0=interior`, `2=inlet/farfield ramp`, `3=outlet`, `4=obstacle wall` | |
| | `data` | `[1, N, 3610]` | `float32` | Legacy DGN-compatible packed tensor; prefer the explicit datasets above | |
| | `diagnostics/compact_iterations` | `[T]` | `uint64` | OpenLB compact-stream iteration identity | |
| | `diagnostics/inlet_ramp_scale` | `[T]` | `float64` | Applied fifth-order ramp scale | |
| | `diagnostics/lbm_density` | `[T, N]` | `float32` | Sampled LBM density | |
| | `diagnostics/physical_time` | `[T]` | `float64` | Solver physical time | |
| | `diagnostics/openlb_sampling_points` | `[N, 2]` | `float32` | OpenLB sampling coordinates | |
| | `diagnostics/nearest_material` | `[N]` | `uint8` | Nearest OpenLB material code | |
| | `diagnostics/*residual` | `[T]` | `float64` | Pressure/streamfunction recovery diagnostics | |
|
|
| Important root attributes include the accepted case identity, geometry family, |
| split, Reynolds number, solver spacings, pressure semantics, contour identities, |
| and sanitized source-code identities represented in `metadata/cases.jsonl`. |
|
|
| ## Pressure semantics |
|
|
| `p` is density-normalized specific pressure recovered from the unsteady |
| Navier--Stokes relation |
|
|
| $$ |
| \nabla p = -\partial_t \mathbf{u} - (\mathbf{u}\cdot\nabla)\mathbf{u} |
| + \nu \nabla^2\mathbf{u}. |
| $$ |
| |
| The supplied fluid-triangle topology is used and the right outlet is the exact |
| zero-pressure gauge. It is not a direct raw OpenLB pressure field. |
| |
