Public evidence

physics.fluid.valve_cv

Machine-checked verification for calculation version 1.0.0 · tier engine_tested

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Verification

17/17 calculation tests · Production surface contract 3/3

Golden tests 2 / 2
Boundary tests 10 / 10
Property tests 5 / 5
Production surface contract 3 / 3
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; 163 CURRENT) @ 2026-09-17T06:27:56.932Z
Semantic contract PASS
Evidence attested at 2026-09-17T06:27:56.176Z
Last production check 2026-09-17T06:27:56.176Z
Public / cache PASS
Origin PASS
Supplemental domain review Not performed
Named expert review Not performed

release artifacts aligned PASS
schema valid input executes PASS
engine success output validates schema PASS

Fingerprint sha256:d4789ab3e4028776421f6e45c57d69b7d91e268116dfb37f88d6b000b21bcec7

Input schema sha256:d38cd4dee167c35753ba3e0e80283228a6156ce20f1427cfb683c53a4380dcf4 · Output schema sha256:c10b35f24095413db98c2410feefd666b46121f52b69ec7e99fa3ae235b5a7f2 · 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.

Build & scope

Engine identity and declared limitations.

Tool: valve-flow-coefficient
Engine: valve-flow-coefficient
Engine build: 2026-09-17
Evidence core: 2026-09-17T05:39:40.082Z
Rendered: 2026-09-17T06:35:12.148Z
Last reviewed: —

Assumptions

Incompressible liquid; Q_m³/h = Kv √(Δp_bar/SG); default SG=1
Kv = 0.865 Cv (IEC 60534-1); frozen, not a US-gpm engine
Not gas, not choked, not IEC 60534-2-1 xT/Y
Not a venturi, not an orifice, not Q=Av, not Darcy, not minor-loss K

Limitations

Incompressible liquid valve: Q_m³/h = Kv √(Δp_bar/SG); Kv = 0.865 Cv (IEC 60534-1)
SI Q in m³/s, Δp in Pa; default SG=1 (water); not gas, not choked
Not a venturi, not an orifice, not Q=Av, not Darcy, not minor-loss K

Sources

Standards and references supporting this tool specification. Methods are listed separately — they are algorithms, not bibliographic sources.

IEC 60534-1 — Industrial-process control valves — Flow capacity — Kv and the Kv–Cv relation
Supports: Kv is m³/h of water at 1 bar; Kv = 0.865 Cv; this page is liquid incompressible only
ISA-75.01.01 — Flow Equations for Sizing Control Valves — Liquid sizing with Cv
Supports: Incompressible liquid Q ∝ Cv √(ΔP/G); gas and choked corrections are out of scope here

Published checks

Golden, boundary, and property cases included in this evidence build.

ID	Kind	Status	Detail
`golden-vcv-q`	golden	pass	Expected Q=0.002777777777777778 · Kv=10 · Cv=11.560693641618498 · SG=1 · Q_m3_h=10 · mode=flow · model=valve_cv · Actual mode=flow · Q=0.002777777777777778 · Q_m3_h=10 · dP=100000 · SG=1 · Kv=10 · Cv=11.560693641618498 · k=0.865
`golden-vcv-cv`	golden	pass	Expected Q=0.002777777777777778 · Kv=10 · model=valve_cv · Actual mode=flow · Q=0.002777777777777778 · Q_m3_h=10 · dP=100000 · SG=1 · Kv=10 · Cv=11.560693641618498 · k=0.865
`boundary-vcv-dp`	boundary	pass	Expected dP=100000 · model=valve_cv · Actual mode=pressure · Q=0.002777777777777778 · Q_m3_h=10 · dP=100000 · SG=1 · Kv=10 · Cv=11.560693641618498 · k=0.865
`boundary-vcv-kv`	boundary	pass	Expected Kv=10 · model=valve_cv · Actual mode=Kv · Q=0.002777777777777778 · Q_m3_h=10 · dP=100000 · SG=1 · Kv=10 · Cv=11.560693641618498 · k=0.865
`boundary-vcv-sg`	boundary	pass	Expected Q=0.001388888888888889 · SG=4 · model=valve_cv · Actual mode=flow · Q=0.001388888888888889 · Q_m3_h=5 · dP=100000 · SG=4 · Kv=10 · Cv=11.560693641618498 · k=0.865
`boundary-vcv-missing`	boundary	pass	Expected MISSING_REQUIRED_INPUT · Actual MISSING_REQUIRED_INPUT
`boundary-vcv-kv0`	boundary	pass	Expected VALUE_MUST_BE_POSITIVE · Actual VALUE_MUST_BE_POSITIVE
`boundary-vcv-both`	boundary	pass	Expected MIXED_INPUT_ENCODING · Actual MIXED_INPUT_ENCODING
`boundary-vcv-d1`	boundary	pass	Expected MIXED_INPUT_ENCODING · Actual MIXED_INPUT_ENCODING
`boundary-vcv-qav`	boundary	pass	Expected MIXED_INPUT_ENCODING · Actual MIXED_INPUT_ENCODING
`boundary-vcv-venturi`	boundary	pass	Expected INVALID_MODE · Actual INVALID_MODE
`boundary-vcv-k`	boundary	pass	Expected MIXED_INPUT_ENCODING · Actual MIXED_INPUT_ENCODING
`property-vcv-q`	property	pass	Kv √(Δp_bar)/3600
`property-vcv-cv`	property	pass	Kv=0.865 Cv
`property-vcv-roundtrip-dp`	property	pass	Δp invert
`property-vcv-sg`	property	pass	Q ∝ 1/√SG
`property-vcv-model`	property	pass	valve_cv