Minor Losses (K-factor) Calculator implementation

Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

Record owner

Guth Instruments

Lifecycle

verified-clean

Evidence ID

t7-070

Effect

Computation or source lookup only

Input and validation requirements

The equivalent-length output requires D and f, but the declared input list only specifies fitting K values and V. In addition, f=0 produces an undefined result and must be explicitly rejected. Without validation and without required D and f inputs, the instrument cannot reliably compute every advertised output.

Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

{
  "inputs": {
    "fitting_list": [
      {
        "name": "sharp-edged entrance",
        "K": 0.5
      }
    ],
    "V_m_per_s": 2,
    "D_m": 0.1,
    "Darcy_friction_factor": 0.02,
    "g_m_per_s2": 9.80665
  },
  "expected_outputs": {
    "total_K": 0.5,
    "total_minor_head_loss_m": 0.101972,
    "equivalent_length_m": 2.5
  },
  "reference_data": {
    "table_rows": [
      {
        "fitting": "sharp-edged entrance",
        "K": 0.5,
        "source_convention": "widely tabulated standard value; Crane TP-410-style loss-coefficient convention"
      }
    ],
    "gravity_m_per_s2": 9.80665,
    "gravity_source_convention": "widely tabulated standard value; standard gravity"
  },
  "working": "K_total = 0.5. 2g = 2 × 9.80665 = 19.6133 m/s². V² = 2.0² = 4. hL = 0.5 × 4 / 19.6133 = 2 / 19.6133 = 0.101972 m. L_eq = K_total × D / f = 0.5 × 0.1 / 0.02 = 0.05 / 0.02 = 2.5 m."
}

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche7/tranche7-results.json