Carnot Efficiency Calculator

Inspectable records

Ledger state

The current ledger marks this instrument verified clean within the source-bound verification corpus.

Area

Thermodynamics, Fluids & Aero

Tranche

tranche-2

Evidence ID

t2-036

Ledger rows

1

No ledger note is attached.

Review findings

The honest label is appropriate: this is a reversible Carnot upper bound, not an achievable efficiency for real engines. Verdict is NEEDS_REVIEW because the input temperature units and the ratio-to-percent conversion are not explicitly specified, and the required Th>Tc≥0 K constraint is omitted.

Formula and scope findings

• The Carnot efficiency formula η=1−Tc/Th is correct for a reversible heat engine when Tc and Th are absolute temperatures and Th>Tc.
• The formula returns a dimensionless ratio; the stated percentage output requires an explicit conversion η_percent=100×(1−Tc/Th).
• The specification does not explicitly state the required validity constraint Th>Tc≥0 K. Inputs with Th≤Tc are invalid for the claimed heat-engine calculation.

Unit assumptions

• Th and Tc must be absolute temperatures in kelvins, or another absolute scale with the same ratio behavior.
• If users enter Celsius or Fahrenheit, values must be converted to kelvins before applying the formula: T(K)=T(°C)+273.15 and T(K)=(T(°F)+459.67)×5/9.
• η is dimensionless; η (%) is the dimensionless result multiplied by 100.
• Maximum work per unit heat input is W_max/Q_in=η, so for 1 unit of heat input the maximum work is η units.

Boundary hardening

BREAK_CLAIMED · SELF_FLAGGED

The specification exposes a division-by-zero input at Th=0 and a physically invalid reversed-temperature ordering that produces a negative raw efficiency. A robust calculator must reject both rather than display misleading numeric results.

Errata and corrections

No applied erratum is attached to this unique-name record.

Inspectable example

4 review vectors are recorded. One source-bound sample is shown below.

{
  "inputs": {
    "Th": 600,
    "Tc": 300,
    "temperature_unit": "K"
  },
  "expected_outputs": {
    "eta_ratio": 0.5,
    "eta_percent": 50,
    "max_work_per_unit_heat": 0.5
  },
  "working": "η=1−Tc/Th=1−300/600=1−0.5=0.5. η_percent=100×0.5=50%. For 1 unit of heat input, W_max/Q_in=0.5, so W_max=0.5 unit."
}

Related workflows

Sources and evidence

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

• VERIFIED_LEDGER.json · VERIFIED_CLEAN
• evidence-tranche2/tranche2-results.json
• BOUNDARY_HAZARD_CATALOG.json