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  "failed": 0,
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      "passed": 2
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    "boundary": {
      "total": 10,
      "passed": 10
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    "property": {
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      "passed": 5
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  "expert_reviewed": false,
  "internally_reviewed": false,
  "review_kind": null,
  "source_checked": true,
  "reviewed_by": null,
  "reviewer_role": null,
  "last_reviewed": null,
  "expert_review": {
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    "reviewer": null,
    "scope": [
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      "input semantics",
      "assumptions",
      "limitations",
      "sources",
      "tests"
    ],
    "note": "Domain expert review is optional under CVP (CVP-EXP-01). Absence does not block CVP Verified. See Review policy for supplemental domain assurance."
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  "assumptions": [
    "Cavitation number σ = (p − p_v) / (½ ρ v²); default ρ=1000 kg/m³; p and p_v absolute Pa",
    "Not NPSH head, not Thoma σ_Th=NPSH/H, not Weber We=ρv²L/σ, not Euler Eu=Δp/(ρ v²)",
    "Not Reynolds, not capillary Ca=μv/σ, not Q=Av"
  ],
  "limitations": [
    "Cavitation number σ = (p − p_v) / (½ ρ v²); default ρ=1000 kg/m³; p and p_v absolute Pa",
    "Not NPSH head, not Thoma σ_Th=NPSH/H, not Weber We=ρv²L/σ, not Euler Eu=Δp/(ρ v²)",
    "Not Reynolds, not capillary Ca=μv/σ, not Q=Av"
  ],
  "boundary_conditions": [
    "missing p, p_v, v, or σ when required → MISSING_REQUIRED_INPUT",
    "p, v, ρ, or σ ≤ 0 → VALUE_MUST_BE_POSITIVE",
    "p ≤ p_v → VALUE_OUT_OF_RANGE",
    "NPSH/z/hf/H/g, We/L, Re/μ, Eu/Δp, A/Q → MIXED_INPUT_ENCODING",
    "npsh, thoma, weber, or euler as mode → INVALID_MODE"
  ],
  "sources": [
    {
      "title": "ISO 80000-11 — Characteristic numbers",
      "section": "Cavitation number",
      "supports": "σ = (p − p_v) / (½ ρ v²); inertia vs vapor-pressure deficit, not NPSH head",
      "kind": "standard"
    },
    {
      "title": "ISO 80000-4 — Mechanics",
      "section": "Pressure",
      "url": "https://www.iso.org/standard/31895.html",
      "supports": "p and p_v are absolute pressures; ½ ρ v² is a dynamic pressure",
      "kind": "standard"
    }
  ],
  "methods": [],
  "fingerprint": "sha256:e3a671d157787e92a9fd358d26c296bd4973b85bb67f82eee6af140f281bd7b5",
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    {
      "id": "golden-cav-sigma",
      "ok": true,
      "kind": "golden",
      "inputs": {
        "p": 150000,
        "p_v": 50000,
        "v": 10
      },
      "expect": {
        "sigma": 2,
        "p": 150000,
        "p_v": 50000,
        "rho": 1000,
        "v": 10,
        "mode": "number",
        "model": "cavitation"
      },
      "expectWarning": null,
      "actual": {
        "mode": "number",
        "sigma": 2,
        "p": 150000,
        "p_v": 50000,
        "rho": 1000,
        "v": 10,
        "model": "cavitation"
      },
      "tol": 1e-12
    },
    {
      "id": "golden-cav-p",
      "ok": true,
      "kind": "golden",
      "inputs": {
        "mode": "pressure",
        "sigma": 2,
        "p_v": 50000,
        "v": 10
      },
      "expect": {
        "p": 150000,
        "model": "cavitation"
      },
      "expectWarning": null,
      "actual": {
        "mode": "pressure",
        "sigma": 2,
        "p": 150000,
        "p_v": 50000,
        "rho": 1000,
        "v": 10,
        "model": "cavitation"
      },
      "tol": 1e-12
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    {
      "id": "boundary-cav-v",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "mode": "velocity",
        "sigma": 2,
        "p": 150000,
        "p_v": 50000
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      "expect": {
        "v": 10,
        "model": "cavitation"
      },
      "expectWarning": null,
      "actual": {
        "mode": "velocity",
        "sigma": 2,
        "p": 150000,
        "p_v": 50000,
        "rho": 1000,
        "v": 10,
        "model": "cavitation"
      },
      "tol": 1e-12
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    {
      "id": "boundary-cav-missing",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "p": 150000,
        "p_v": 50000
      },
      "expectError": "MISSING_REQUIRED_INPUT",
      "code": "MISSING_REQUIRED_INPUT",
      "error": "v is required"
    },
    {
      "id": "boundary-cav-npsh",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "p": 150000,
        "p_v": 50000,
        "v": 10,
        "NPSH": 10
      },
      "expectError": "MIXED_INPUT_ENCODING",
      "code": "MIXED_INPUT_ENCODING",
      "error": "Cavitation number is not NPSH head. That is /calc/physics/npsh"
    },
    {
      "id": "boundary-cav-We",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "p": 150000,
        "p_v": 50000,
        "v": 10,
        "We": 1000
      },
      "expectError": "MIXED_INPUT_ENCODING",
      "code": "MIXED_INPUT_ENCODING",
      "error": "Cavitation number does not take Weber We, L, or σ as N/m. That is /calc/physics/weber-number"
    },
    {
      "id": "boundary-cav-Re",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "p": 150000,
        "p_v": 50000,
        "v": 10,
        "Re": 100000
      },
      "expectError": "MIXED_INPUT_ENCODING",
      "code": "MIXED_INPUT_ENCODING",
      "error": "Cavitation number does not take Re, μ, ν, or Fr. Not Reynolds, not capillary Ca=μv/σ"
    },
    {
      "id": "boundary-cav-A",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "p": 150000,
        "p_v": 50000,
        "v": 10,
        "A": 1
      },
      "expectError": "MIXED_INPUT_ENCODING",
      "code": "MIXED_INPUT_ENCODING",
      "error": "Cavitation number does not take Q=Av A/Q. That is /calc/physics/flow-rate"
    },
    {
      "id": "boundary-cav-dP",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "p": 150000,
        "p_v": 50000,
        "v": 10,
        "dP": 100000
      },
      "expectError": "MIXED_INPUT_ENCODING",
      "code": "MIXED_INPUT_ENCODING",
      "error": "Cavitation number is not Euler Eu=Δp/(ρ v²). Send p and p_v, not a single Δp"
    },
    {
      "id": "boundary-cav-mode",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "p": 150000,
        "p_v": 50000,
        "v": 10,
        "mode": "npsh"
      },
      "expectError": "INVALID_MODE",
      "code": "INVALID_MODE",
      "error": "mode must be number|pressure|vapor|velocity. Not NPSH, Thoma, Weber, Euler, or Q=Av"
    },
    {
      "id": "boundary-cav-zero",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "p": 150000,
        "p_v": 50000,
        "v": 0
      },
      "expectError": "VALUE_MUST_BE_POSITIVE",
      "code": "VALUE_MUST_BE_POSITIVE",
      "error": "v must be greater than zero"
    },
    {
      "id": "boundary-cav-margin",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "p": 50000,
        "p_v": 50000,
        "v": 10
      },
      "expectError": "VALUE_OUT_OF_RANGE",
      "code": "VALUE_OUT_OF_RANGE",
      "error": "Cavitation number needs p > p_v"
    },
    {
      "id": "property-cav-sigma",
      "ok": true,
      "kind": "property",
      "detail": "σ=(p−p_v)/(½ρv²)",
      "expect": 2,
      "actual": 2
    },
    {
      "id": "property-cav-roundtrip-p",
      "ok": true,
      "kind": "property",
      "detail": "p invert",
      "expect": 150000,
      "actual": 150000
    },
    {
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      "ok": true,
      "kind": "property",
      "detail": "v invert",
      "expect": 10,
      "actual": 10
    },
    {
      "id": "property-cav-rho",
      "ok": true,
      "kind": "property",
      "detail": "ρ default 1000",
      "expect": 1000,
      "actual": 1000
    },
    {
      "id": "property-cav-model",
      "ok": true,
      "kind": "property",
      "detail": "cavitation",
      "expect": true,
      "actual": "cavitation"
    }
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      "total": 17,
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      "boundary": 10,
      "property": 5
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