Thermal Resistance Conduction⚠ unverified
Physics / Heat Transfer · Compute the thermal resistance of a conducting layer
Parameters
| Input | Symbol | Unit | Default | Description |
|---|---|---|---|---|
| L | L | m | 1.0 | Thickness of the layer along the heat-flow direction |
| k | k | — | 1.0 | Thermal conductivity of the material, in watts per metre-kelvin (W/(m*K)) |
| A | A | m**2 | 1.0 | Cross-sectional area normal to heat flow |
| Output | Symbol | Unit | Description |
|---|---|---|---|
| result | R | K/W | Conduction thermal resistance, in kelvin per watt (K/W). Returns positive infinity when the product ``k * A`` is not positive |
The science & history
Understanding the Parameters
- $L$, $k$, $A$ — thicker, less conductive, or smaller area → larger $R$.
- $k$ may be mislabelled dimensionless in the registry.
- $R$ — add in series for layered walls; parallel for side-by-side paths (with care).
Derivation (Approaching a Proof)
From $Q = k A \Delta T / L$, identify $R \equiv \Delta T/Q = L/(kA)$. Electrical analogy: $V \leftrightarrow \Delta T$, $I \leftrightarrow Q$, $R$ thermal.
History
Thermal-resistance networks are the standard building and electronics cooling bookkeeping method.
Related Concepts: 1D Steady Conduction, Thermal Resistance Convection, Overall Heat Transfer Coefficient, Thermal Resistance Jc
Notes: Registry calculator thermal-resistance-conduction (unverified). Plane wall.