1. What is Thermal Conductivity?

Definition: Thermal conductivity (k) measures a material's ability to conduct heat. It's the quantity of heat transmitted through a unit thickness in a direction normal to a surface of unit area.

Purpose: This calculation is essential for thermal insulation, heat exchanger design, and building material selection.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( k \) — Thermal conductivity (W/m K)
• \( Q \) — Heat transfer rate (W)
• \( L \) — Length of material (m)
• \( A \) — Cross-sectional area (m²)
• \( \Delta T \) — Temperature difference (K)

Explanation: The formula calculates how easily heat flows through a material based on the heat input, material dimensions, and temperature difference.

3. Importance of Thermal Conductivity

Details: Understanding thermal conductivity helps in selecting appropriate materials for insulation, heat dissipation, and energy-efficient building design.

4. Using the Calculator

Tips: Enter the heat transfer rate in watts, material length in meters, cross-sectional area in square meters, and temperature difference in Kelvin. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What are typical thermal conductivity values?
A: Copper ≈ 400 W/m K, aluminum ≈ 200 W/m K, glass ≈ 1 W/m K, wood ≈ 0.1 W/m K.

Q2: How does temperature affect conductivity?
A: For metals, conductivity decreases with temperature; for insulators, it may increase.

Q3: What's the difference between K and °C in ΔT?
A: For temperature differences, 1 K = 1°C, so either unit can be used.

Q4: How do I measure heat transfer rate (Q)?
A: Use a heat flux sensor or calculate from power input in controlled experiments.

Q5: What if my material isn't uniform?
A: This calculator assumes homogeneous materials. For composites, use effective thermal conductivity formulas.