Verification
5/5 calculation tests · Production surface contract 1/1
- Golden tests 0 / 0
- Boundary tests 0 / 0
- Property tests 5 / 5
- Production surface contract 1 / 1
}
- Engine tested Yes
- Source checked Yes
- Artifact integrity PASS
- Production attestation Embedded snapshot: STALE · Last attested schema matched 1.0.0 snapshot / local build · Semantic contract ✓ · Last attestation PASS · current evidence changed · re-attestation required · Public/cache ✓ · Origin ✓ · Live production status PASS (0 stale; 164 CURRENT) @ 2026-09-18T10:48:34.503Z
- Semantic contract PASS
- Evidence attested at 2026-09-18T10:48:33.674Z
- Last production check 2026-09-18T10:48:33.674Z
- Public / cache PASS
- Origin PASS
- Supplemental domain review Not performed
- Named expert review Not performed
- release artifacts aligned PASS
Fingerprint sha256:f1e4a74fd77d167a58a0a32c15be491f2653b7f4d77325394937dc72e22c8c2e
Input schema sha256:d165c2c6ae6fff639a9cfddb386dc3931489788dc28513c80e2dde8e26c66b4e · Output schema sha256:9de1df83acdc3768f75be3c172b05aa4391a6a48e2ee2fbdaa0430972a1aa356 · Build-time SHA-256 digests prove published artifacts agree with each other (release_integrity.scope=workspace). Production attestation GETs canonical URLs twice (public/cached view and origin), including Capability HTML, via npm run attest:production --write
(published at /.well-known/calculatorx-production-attestation.json) and fails if the public Capability page advertises a different calculation_version. This is artifact consistency, not an independent immutable release log.
Engine identity and declared limitations.
- Tool
- elbow-meter
- Engine
- elbow-meter
- Engine build
- 2026-09-18
- Evidence core
- 2026-09-18T10:34:57.880Z
- Rendered
- 2026-09-18T11:10:25.556Z
- Last reviewed
- —
Assumptions
- 90° elbow tap meter: Q = C A √(2Δp/ρ); C=√((R/D)/2); A=(π/4)D²; inner/outer radius taps; incompressible; C is reported, not an input
- R/D∈[1.0, 3.0]; D∈[25 mm, 600 mm]; 90° only; C from R/D, not a given Pitot C=1
- Not pipe-bend K=0.21 (θ/90)/√(R/D), not Pitot v=C√(2Δp/ρ), not venturi, not ISO 5167-6 wedge, not Q=Av, not Darcy f
Limitations
- 90° elbow tap meter: Q = C A √(2Δp/ρ); C=√((R/D)/2); A=(π/4)D²; inner/outer radius taps; incompressible; C is reported, not an input
- R/D∈[1.0, 3.0]; D∈[25 mm, 600 mm]; 90° only; C from R/D, not a given Pitot C=1
- Not pipe-bend K=0.21 (θ/90)/√(R/D), not Pitot v=C√(2Δp/ρ), not venturi, not ISO 5167-6 wedge, not Q=Av, not Darcy f
Sources
Standards and references supporting this tool specification. Methods are listed separately — they are algorithms, not bibliographic sources.
- ISO 80000-4 — Mechanics — Length, speed, pressure
Supports: D and R are lengths; Q is a volume flow; Δp is a pressure
- Elbow tap meter — centrifugal Δp — C=√((R/D)/2) from inner/outer taps
Supports: Q=C A √(2Δp/ρ) with C=√((R/D)/2); 90° only. Not pipe-bend K, not Pitot C=1, not venturi, not ISO 5167-6 wedge
Published checks
Golden, boundary, and property cases included in this evidence build.
| ID | Kind | Status | Detail |
|---|
property-elb-C | property | pass | C=√((R/D)/2) |
property-elb-Q | property | pass | Q=C A √(2Δp/ρ) |
property-elb-not-pitot | property | pass | C≠Pitot 1 |
property-elb-roundtrip-dP | property | pass | Δp invert |
property-elb-model | property | pass | elbow_tap_90 |
