Heat Transfer Rate Calculator (Conduction)
Calculate thermal energy flow through solid materials using Fourier's Law
W/m·K
m²
°C/K
m
Calculation Result
Understanding Heat Transfer Rate (Conduction)
In thermodynamics, the heat transfer rate refers to the amount of thermal energy moving through a material per unit of time. This calculator specifically uses Fourier's Law of Thermal Conduction, which describes how heat moves through solid materials from a high-temperature zone to a low-temperature zone.
The Heat Transfer Formula
The calculation is based on the following mathematical formula:
Q = (k × A × ΔT) / L
- Q: Heat Transfer Rate (Watts or Joules per second)
- k: Thermal Conductivity of the material (W/m·K)
- A: Surface area perpendicular to the heat flow (m²)
- ΔT: Temperature difference between the two surfaces (T_hot – T_cold)
- L: Thickness or length of the material through which heat travels (m)
Practical Example
Suppose you are analyzing a wall made of fiberglass insulation. You have the following data:
- ✅ Thermal Conductivity: 0.04 W/m·K
- ✅ Wall Area: 20 m²
- ✅ Outside vs Inside Temp: 30°C difference
- ✅ Insulation Thickness: 0.15 meters
Plugging these into the formula: (0.04 × 20 × 30) / 0.15 = 160 Watts. This means the wall loses 160 Joules of energy every second through conduction.
Typical Thermal Conductivity Values (k)
| Material | Conductivity (W/m·K) |
|---|---|
| Copper | 401.0 |
| Aluminum | 205.0 |
| Concrete | 0.8 – 1.3 |
| Glass | 0.8 – 0.9 |
| Wood | 0.12 – 0.15 |
| Fiberglass Insulation | 0.04 |