1. What is Thermal Conductivity?

Thermal conductivity (k) is a measure of a material's ability to conduct heat. It is defined as the quantity of heat transmitted through a unit thickness in a direction normal to a surface of unit area, due to a unit temperature gradient under steady state conditions.

2. How Does the Calculator Work?

The calculator uses the thermal conductivity equation:

Where:

• \( k \) — Thermal conductivity (W/m·K)
• \( \rho \) — Material density (kg/m³)
• \( c_p \) — Specific heat capacity (J/kg·K)
• \( \alpha \) — Thermal diffusivity (m²/s)

Explanation: The equation relates the three fundamental thermal properties of a material to determine its ability to conduct heat.

3. Importance of Thermal Conductivity

Details: Thermal conductivity is crucial in building insulation, heat exchanger design, electronic cooling systems, and many engineering applications where heat transfer is important.

4. Using the Calculator

Tips: Enter material density in kg/m³, specific heat in J/kg·K, and thermal diffusivity in m²/s. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What are typical thermal conductivity values?
A: Metals range from 15-400 W/m·K, while insulators are typically 0.01-0.5 W/m·K. Air has very low conductivity (~0.024 W/m·K).

Q2: How does temperature affect thermal conductivity?
A: For metals, conductivity decreases with temperature. For gases and insulators, it generally increases with temperature.

Q3: What's the difference between conductivity and diffusivity?
A: Conductivity measures heat transfer ability, while diffusivity measures how quickly temperature changes propagate through a material.

Q4: Why are UK units used in this calculator?
A: The UK uses SI units (W/m·K) for thermal conductivity, which is the international standard in scientific and engineering contexts.

Q5: Can this calculator be used for anisotropic materials?
A: No, this simple calculator assumes isotropic materials where conductivity is the same in all directions.