physics.fluid.colebrook

Three distinct suites: educational examples on the calculator page, this legacy regression count (9/9 golden + boundary), and the CVP verification suite below. They are not the same number. Property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the CVP Manifest . SKIP (0/0) means that suite has no published vectors.

This calculator CURRENT · Public schema 1.0.0 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓

CVP verification suite

Protocol checks from the Evidence Manifest. Distinct from the legacy regression suite above. Verification revision 2026-10-28.meta-metrics-v2. Calculation version 1.0.0. CVP 1.0.0-proposed. 5/5 golden · 6/6 CVP boundary · 5/5 invalid · 1/1 property · 1/1 metamorphic · 8/8 O3 · 2/2 cross-interface · 6/6 CVP contract. digest 64f236e42ea5. O2: Colebrook–White 1/√f = −2 log10(ε/D/3.7 + 2.51/(Re√f)) via Haaland start + Newton on √f (≤2 ULP). Not Darcy hf, not laminar 64/Re, and not Swamee–Jain as the product. ≤2 ULP vs O3 applies only to the published tabulated Colebrook vectors. Not Darcy hf and not laminar 64/Re.

• Golden (oracle-backed) 5 / 5
• CVP boundary 6 / 6
• Invalid input 5 / 5
• Property 1 / 1
• Metamorphic 1 / 1
• O3 high-precision 8 / 8
• Cross-interface 2 / 2
• CVP contract 6 / 6
• Interfaces PASS · UI (SSR) / REST / MCP
• Interface claim ui-ssr is query-result HTML, not a live browser session. Error-path engine·REST·MCP 1/1 (status, code, calculation_version). SSR compared on URL-canonical requested calculations; empty query is idle (not an error) and JSON-typed object/array inputs are REST/MCP-only.
• Verified scope Colebrook–White turbulent f from Re and ε/D; + O3 tabulated f.
• Assurance Engineering
• Deferred Not Darcy hf from given f, not laminar 64/Re, and not Swamee–Jain as the product.

• release artifacts aligned PASS
• schema output required declared PASS
• schema valid input executes PASS
• engine success output validates schema PASS
• schema rejects incomplete input PASS
• rest success payload validates schema PASS

Fingerprint sha256:d9eae29ee96f8f982c9d408d79a6592f0f95df4fb4080138a201f8026c96821a

Input schema sha256:3e523ba459b82af86a656a663688e2321e8b4a9592f9c1c2ff0745ff4ee5f09f · Output schema sha256:cd6d361ae837cd914f7c599c1f47a85cac544494a582e3e14d95dcd625ed27f8 · 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.

Tool

colebrook

Engine

colebrook

Engine build

2026-09-16

Evidence core

2026-09-16T08:17:21.133Z

Rendered

2026-11-10T05:18:41.917Z

Last reviewed

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Assumptions

• Turbulent circular full-flow pipe, Re ≥ 4000
• Incompressible; constant properties
• Not laminar 64/Re
• Not a Moody-chart lookup
• Does not compose Darcy head loss or Reynolds

Limitations

• Turbulent pipes Re ≥ 4000 — not laminar f=64/Re
• Not a Moody-chart lookup
• Does not compose Darcy–Weisbach head loss