Biot Number / Lumped Capacitance Validity Check 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

t4-204

Effect

Computation or source lookup only

Input and validation requirements

A zero thermal-conductivity input causes division by zero and an undefined Bi unless explicitly rejected. A separate convention ambiguity can also change the validity result from pass to fail.

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": {
    "h": 25,
    "Lc": 0.01,
    "k": 0.5,
    "units": "h in W/(m^2·K), Lc in m, k in W/(m·K)"
  },
  "expected_outputs": {
    "Bi": 0.5,
    "valid": "FAIL"
  },
  "working": "Bi = hLc/k = (25 × 0.01) / 0.5 = 0.25 / 0.5 = 0.5. Since 0.5 is not less than 0.1, valid = FAIL."
}

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-tranche4/tranche4-results.json