Thermodynamics
Heat Conduction
Rate of heat flow through a material.
Variables
PW
Heat flow rate
Power (energy/time)
In SI units: kg·m²/s³
kW/(m·K)
Thermal conductivity
Material property
In SI units: kg·m/(s³·K)
Allowed values: greater than 0
Am²
Cross-sectional area
Area of heat flow
Allowed values: greater than 0
ΔTK
Temperature difference
Hot - cold
Lm
Length
Distance heat travels
Allowed values: greater than 0
Derivation
Fourier's law of heat conduction.
Your notes
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Check value
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- k = 2 W/(m·K) (Thermal conductivity)
- A = 3 m² (Cross-sectional area)
- ΔT = 4 K (Temperature difference)
- L = 5 m (Length)
Result: P = 4.8 W
Other thermodynamics formulas with the same quantities
- Thermal Resistance (Heat & Temperature) shares Length, Thermal conductivity, Cross-sectional area
Where this formula is listed
- Thermodynamics formulas, under Heat & Temperature, alongside Heat Capacity, Latent Heat, Linear Thermal Expansion, Volume Thermal Expansion and Newton's Law of Cooling.
- In the thermodynamics list it comes after Volume Thermal Expansion and before Stefan-Boltzmann Law.
- Thermodynamics formula sheet, one of 34 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Heat Conduction formula?
Heat Conduction is written P = kAΔT/L. Rate of heat flow through a material. It belongs to Thermodynamics, under Heat & Temperature.
What are the units in P = kAΔT/L?
In SI units, P is heat flow rate, measured in kg·m²/s³; k is thermal conductivity, measured in kg·m/(s³·K); A is cross-sectional area, measured in m²; ΔT is temperature difference, measured in K; L is length, measured in m.
How is the Heat Conduction formula derived?
Fourier's law of heat conduction. The result is P = kAΔT/L.