Heat Transfer

Conduction — Flat Plate

Fourier's Law for steady-state conduction through a flat plate — computes heat transfer rate from geometry, temperature difference, and material conductivity.

Inputs

Results

Heat transfer rate (Q)

—

watts

—

Thermal resistance (R)

—

K/W

Heat flux (q)

—

W/m²

—

Insulation R-value

—

hr·ft²·°F / BTU

—

Material reference table

Material ↕ k (W/m·K) ↓ k (BTU/hr·ft·°F) Q at inputs (W)

Fourier's Law — Flat Plate

Q = k · A · ΔT / X
Q = heat transfer rate (W) k = thermal conductivity (W/m·K) A = cross-sectional area (m²) ΔT = temperature difference (K or °C) X = plate thickness (m) R (SI) = X / (k·A) — thermal resistance (K/W) R (imperial) = Xft / kBTU — insulation R-value (hr·ft²·°F/BTU)