physics.fluid.pipe_cross

• Golden tests 0 / 0
• Boundary tests 0 / 0
• Property tests 6 / 6
• 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 STALE (1 capability; 163 remain CURRENT) @ 2026-09-17T23:16:16.380Z
• Semantic contract PASS
• Evidence attested at 2026-09-17T23:04:34.157Z
• Last production check 2026-09-17T23:04:34.157Z
• Public / cache PASS
• Origin PASS
• Supplemental domain review Not performed
• Named expert review Not performed

• release artifacts aligned PASS

Fingerprint sha256:e6825a635217ce5b6215bb34d54e012d45d2012bc810e01c6d884fd28922308f

Input schema sha256:e09751c8657bf28592452d5c79cc9837052f643e13a3ab812859d276cc9fd736 · Output schema sha256:55b6d41a7aff16b41155d013448caca5c0c9854e5ea875eca171a36b56b01ada · 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

pipe-cross

Engine

pipe-cross

Engine build

2026-09-17

Evidence core

2026-09-17T22:32:28.651Z

Rendered

2026-09-17T23:36:55.415Z

Last reviewed

—

Assumptions

• Equal-area sharp 90° four-way cross: h = K v_c² / (2g); K referenced to common-channel speed; two opposite laterals are equal; K is reported, not an input
• Dividing: branch K=(1+q)², run K=0.4(1−q)². Combining: branch K=1+q²−4(1−2q)²/(2−q), run K=1+q²−q²/[1+q(0.75+0.25q)²]. Branch q≤0.5; default g=9.80665 m/s²; default ρ=1000 kg/m³
• Not a 90° tee, not a non-90° wye, not catalog minor-loss K given, not circular-arc R/D, not mitered n, not pipe-entrance geometry, not pipe-exit K=1, not Q=Av

Limitations

• Equal-area sharp 90° four-way cross: h = K v_c² / (2g); K referenced to common-channel speed; two opposite laterals are equal; K is reported, not an input
• Dividing: branch K=(1+q)², run K=0.4(1−q)². Combining: branch K=1+q²−4(1−2q)²/(2−q), run K=1+q²−q²/[1+q(0.75+0.25q)²]. Branch q≤0.5; default g=9.80665; default ρ=1000 for Δp
• Not a 90° tee, not a non-90° wye, not catalog minor-loss K given, not circular-arc R/D, not mitered n, not pipe-entrance geometry, not pipe-exit K=1, not Q=Av