Website Rev 1.1 · retained evidence · not a new solver run
Axisymmetric nozzle: a first-cut numerical study
Numerical result: PASS. Design readiness: NOT ESTABLISHED.
1. Question & acceptance criterion
How sensitive is predicted pressure drop to refinement? Compare three grids against the predeclared 2% adjacent-grid limit. This is a mesh-sensitivity test, not experimental validation.
2. Geometry & model
The retained case uses a one-degree axisymmetric wedge. The full 3D nozzle on the landing page is an illustrative geometry, not a claim of a full-annulus CFD run.
- converging length m
- 0.045
- diverging length m
- 0.11
- exit radius m
- 0.024
- inlet radius m
- 0.02
- mesh level
- 4
- throat radius m
- 0.008
3. First-principles checks
These equations establish continuity and an ideal-gas density screen. The landing-page slider uses explicitly stated constant-density assumptions; it does not calculate pressure loss, choking or thrust. Its estimates are not substituted for the retained solver outputs.
4. Recorded results
| Level | Volume cells | Pressure drop | Numerical gates |
|---|---|---|---|
| 2 | 6,048 | 446.189 Pa | PASS |
| 3 | 9,072 | 439.529 Pa | PASS |
| 4 | 12,600 | 439.613 Pa | PASS |
Fine-run solver time: 798.2 seconds. Execution status: COMPLETE. These are recorded timings, not a performance promise.
5. Engineering disposition
no validation reference is attached to this case
no model fidelity assessment is recorded for this case
pressure_drop changed at most 1.52% between eligible refinement levels (limit 2.00%)
Do not use this case for design release until the missing independent reference and model-fidelity assessment are resolved. Geometry changes invalidate applicability of the recorded mesh and results.
6. Inspect the source
Authoritative engineering result (JSON) · Published artifact checksums · Guided walkthrough
The earlier first-cut acceptance summary is a different archived study and is not the source of the numbers in this report.