{
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  "failed": 0,
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      "passed": 2
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    "boundary": {
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  "expert_reviewed": false,
  "internally_reviewed": false,
  "review_kind": null,
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  "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"
  ],
  "boundary_conditions": [
    "missing Kv/Cv, Δp, or Q when required → MISSING_REQUIRED_INPUT",
    "Kv, Cv, Δp, Q, or SG ≤ 0 → VALUE_MUST_BE_POSITIVE",
    "Kv and Cv, SG and ρ, D1/D2, C_d, K, A, v, or Q with flow → MIXED_INPUT_ENCODING",
    "venturi, orifice, darcy, or Q=Av as mode → INVALID_MODE"
  ],
  "sources": [
    {
      "title": "IEC 60534-1 — Industrial-process control valves — Flow capacity",
      "section": "Kv and the Kv–Cv relation",
      "url": "https://webstore.iec.ch/publication/2451",
      "supports": "Kv is m³/h of water at 1 bar; Kv = 0.865 Cv; this page is liquid incompressible only",
      "kind": "standard"
    },
    {
      "title": "ISA-75.01.01 — Flow Equations for Sizing Control Valves",
      "section": "Liquid sizing with Cv",
      "supports": "Incompressible liquid Q ∝ Cv √(ΔP/G); gas and choked corrections are out of scope here",
      "kind": "standard"
    }
  ],
  "methods": [],
  "fingerprint": "sha256:d4789ab3e4028776421f6e45c57d69b7d91e268116dfb37f88d6b000b21bcec7",
  "tests": [
    {
      "id": "golden-vcv-q",
      "ok": true,
      "kind": "golden",
      "inputs": {
        "Kv": 10,
        "dP": 100000
      },
      "expect": {
        "Q": 0.002777777777777778,
        "Kv": 10,
        "Cv": 11.560693641618498,
        "SG": 1,
        "Q_m3_h": 10,
        "mode": "flow",
        "model": "valve_cv"
      },
      "expectWarning": null,
      "actual": {
        "mode": "flow",
        "Q": 0.002777777777777778,
        "Q_m3_h": 10,
        "dP": 100000,
        "SG": 1,
        "Kv": 10,
        "Cv": 11.560693641618498,
        "k": 0.865,
        "model": "valve_cv"
      },
      "tol": 1e-12
    },
    {
      "id": "golden-vcv-cv",
      "ok": true,
      "kind": "golden",
      "inputs": {
        "Cv": 11.560693641618498,
        "dP": 100000
      },
      "expect": {
        "Q": 0.002777777777777778,
        "Kv": 10,
        "model": "valve_cv"
      },
      "expectWarning": null,
      "actual": {
        "mode": "flow",
        "Q": 0.002777777777777778,
        "Q_m3_h": 10,
        "dP": 100000,
        "SG": 1,
        "Kv": 10,
        "Cv": 11.560693641618498,
        "k": 0.865,
        "model": "valve_cv"
      },
      "tol": 1e-12
    },
    {
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      "ok": true,
      "kind": "boundary",
      "inputs": {
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        "Kv": 10,
        "Q": 0.002777777777777778
      },
      "expect": {
        "dP": 100000,
        "model": "valve_cv"
      },
      "expectWarning": null,
      "actual": {
        "mode": "pressure",
        "Q": 0.002777777777777778,
        "Q_m3_h": 10,
        "dP": 100000,
        "SG": 1,
        "Kv": 10,
        "Cv": 11.560693641618498,
        "k": 0.865,
        "model": "valve_cv"
      },
      "tol": 1e-12
    },
    {
      "id": "boundary-vcv-kv",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "mode": "Kv",
        "Q": 0.002777777777777778,
        "dP": 100000
      },
      "expect": {
        "Kv": 10,
        "model": "valve_cv"
      },
      "expectWarning": null,
      "actual": {
        "mode": "Kv",
        "Q": 0.002777777777777778,
        "Q_m3_h": 10,
        "dP": 100000,
        "SG": 1,
        "Kv": 10,
        "Cv": 11.560693641618498,
        "k": 0.865,
        "model": "valve_cv"
      },
      "tol": 1e-12
    },
    {
      "id": "boundary-vcv-sg",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "Kv": 10,
        "dP": 100000,
        "SG": 4
      },
      "expect": {
        "Q": 0.001388888888888889,
        "SG": 4,
        "model": "valve_cv"
      },
      "expectWarning": null,
      "actual": {
        "mode": "flow",
        "Q": 0.001388888888888889,
        "Q_m3_h": 5,
        "dP": 100000,
        "SG": 4,
        "Kv": 10,
        "Cv": 11.560693641618498,
        "k": 0.865,
        "model": "valve_cv"
      },
      "tol": 1e-12
    },
    {
      "id": "boundary-vcv-missing",
      "ok": true,
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      },
      "expectError": "MISSING_REQUIRED_INPUT",
      "code": "MISSING_REQUIRED_INPUT",
      "error": "Need Kv or Cv"
    },
    {
      "id": "boundary-vcv-kv0",
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        "dP": 100000
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      "expectError": "VALUE_MUST_BE_POSITIVE",
      "code": "VALUE_MUST_BE_POSITIVE",
      "error": "Kv must be greater than zero"
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    {
      "id": "boundary-vcv-both",
      "ok": true,
      "kind": "boundary",
      "inputs": {
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        "Cv": 11.560693641618498,
        "dP": 100000
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      "expectError": "MIXED_INPUT_ENCODING",
      "code": "MIXED_INPUT_ENCODING",
      "error": "Give Kv or Cv, not both. Kv = 0.865 Cv"
    },
    {
      "id": "boundary-vcv-d1",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "Kv": 10,
        "dP": 100000,
        "D1": 0.1
      },
      "expectError": "MIXED_INPUT_ENCODING",
      "code": "MIXED_INPUT_ENCODING",
      "error": "Valve Cv/Kv does not take venturi D1/D2 or orifice d. That is /calc/physics/venturi or /calc/physics/orifice-discharge"
    },
    {
      "id": "boundary-vcv-qav",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "Kv": 10,
        "dP": 100000,
        "A": 0.002
      },
      "expectError": "MIXED_INPUT_ENCODING",
      "code": "MIXED_INPUT_ENCODING",
      "error": "Valve Cv/Kv does not take Q=Av A or v"
    },
    {
      "id": "boundary-vcv-venturi",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "Kv": 10,
        "dP": 100000,
        "mode": "venturi"
      },
      "expectError": "INVALID_MODE",
      "code": "INVALID_MODE",
      "error": "mode must be flow|pressure|Kv|Cv. Not venturi, orifice, Darcy, or Q=Av"
    },
    {
      "id": "boundary-vcv-k",
      "ok": true,
      "kind": "boundary",
      "inputs": {
        "Kv": 10,
        "dP": 100000,
        "K": 0.5
      },
      "expectError": "MIXED_INPUT_ENCODING",
      "code": "MIXED_INPUT_ENCODING",
      "error": "Valve Cv/Kv does not take minor-loss K. Give Kv or Cv. That is /calc/physics/minor-loss"
    },
    {
      "id": "property-vcv-q",
      "ok": true,
      "kind": "property",
      "detail": "Kv √(Δp_bar)/3600",
      "expect": 0.002777777777777778,
      "actual": 0.002777777777777778
    },
    {
      "id": "property-vcv-cv",
      "ok": true,
      "kind": "property",
      "detail": "Kv=0.865 Cv",
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    {
      "id": "property-vcv-roundtrip-dp",
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      "kind": "property",
      "detail": "Δp invert",
      "expect": 100000,
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    },
    {
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      "kind": "property",
      "detail": "Q ∝ 1/√SG",
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      "actual": 0.5
    },
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      "ok": true,
      "kind": "property",
      "detail": "valve_cv",
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      "actual": "valve_cv"
    }
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