Thermal Conductivity: Definition, Formula & Examples

Key Concepts

What is Thermal Conductivity?

• Definition: Thermal conductivity is the property of a material to conduct heat.
• Coefficient of thermal conductivity (k): Different for each material, determining how effectively it conducts heat.
• Materials:
  • High k: Metals (good conductors)
  • Low k: Wood (poor conductors)

Fourier’s Law of Heat Conduction

• Used to calculate the heat flow in a material.
• Essential for determining the thermal conductivity of an unknown material.

Heat Flow

• Heat always flows from a region of higher temperature to a region of lower temperature.

Examples and Applications

• Materials with high thermal conductivity are efficient in transferring heat and are used in applications where quick heat dissipation is necessary, such as in heatsinks and cooking utensils.
• Materials with low thermal conductivity are used as insulators to prevent heat loss, such as in building insulation.

Formula

• The formula for calculating the rate of heat transfer through a material depends on the material's thermal conductivity, the temperature difference across the material, and the material's dimensions.

Summary

• Understanding thermal conductivity is crucial in designing materials and systems for efficient thermal management in engineering and everyday applications.
• Practical Usage: It is used in designing household items, industrial machinery, and in scientific research to understand and control heat transfer processes.

Related Topics

• Heat Transfer: Involves conduction, convection, and radiation.
• Thermal Gradient: The rate of temperature change in space, which affects heat transfer.
• Latent Heat of Fusion: Amount of heat required to change a substance from solid to liquid at constant temperature.
• Conduction: Direct heat transfer through a material.

Notable Contributors

• Betsy Chesnutt: Ph.D. in biomedical engineering, experience in developing STEM curriculum.
• Michael Blosser: Masters in Physics, experience in teaching various subjects.