Fourier Conduction (Plane Wall) 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-4

Evidence ID

t4-108

Ledger rows

1

No ledger note is attached.

Review findings

The core formula is standard and correct under the stated steady-state 1D plane-wall idealization. The specification needs an explicit heat-flux formula, SI-unit requirements or documented unit conversion, a ΔT sign convention, and input constraints before release.

Formula and scope findings

• The heat-rate formula q = k·A·ΔT/L is correct for steady, one-dimensional conduction through a plane wall with constant thermal conductivity and no internal heat generation.
• The advertised heat-flux output has no explicit formula; it should be q'' = q/A = k·ΔT/L.
• The sign convention for ΔT is unspecified. For signed heat rate, define ΔT = T_hot − T_cold; otherwise the calculator should state that it reports heat-rate magnitude.

Unit assumptions

• Use SI units: k in W/(m·K), area A in m², thickness L in m, and ΔT in K or °C temperature difference; the result q is in W.
• Heat flux q'' is in W/m².
• If non-SI inputs are accepted, the calculator must explicitly convert area and thickness before applying the formula; the current specification does not state whether unit conversion is supported.
• Thermal-conductivity table entries must be in W/(m·K) or be converted to those units.

Boundary hardening

BREAK_CLAIMED · SELF_FLAGGED

The zero-thickness input produces an undefined division-by-zero result and must be rejected. The specification also leaves the sign convention for ΔT and heat-flow direction unstated, allowing results that differ by sign.

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": {
    "k_W_per_mK": 0.6,
    "area_m2": 2.5,
    "thickness_m": 0.1,
    "delta_T_K": 20
  },
  "expected_outputs": {
    "heat_rate_q_W": 300,
    "heat_flux_W_per_m2": 120
  },
  "working": "q = k·A·ΔT/L = 0.6·2.5·20/0.1 = 30/0.1 = 300 W. q'' = q/A = 300/2.5 = 120 W/m²."
}

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-tranche4/tranche4-results.json
• BOUNDARY_HAZARD_CATALOG.json