1. What is Thermal Contact Conductance?

Thermal contact conductance is the study of heat transfer between solid bodies in contact. The contact heat transfer coefficient (h_c) quantifies the efficiency of heat transfer across an interface between two materials in contact.

2. How Does the Calculator Work?

The calculator uses the thermal contact conductance formula:

Where:

• \( h_c \) — Contact heat transfer coefficient (W/m²K)
• \( Q \) — Heat transfer rate (W)
• \( A \) — Contact area (m²)
• \( \Delta T \) — Temperature difference across the interface (K)

Explanation: The formula calculates how effectively heat transfers between two surfaces in contact, considering the heat flow rate, contact area, and temperature difference.

3. Importance of Contact Heat Transfer Coefficient

Details: Accurate calculation of contact heat transfer coefficient is crucial for thermal management in electronics, mechanical systems, building insulation, and various engineering applications where efficient heat dissipation is required.

4. Using the Calculator

Tips: Enter heat transfer rate in watts (W), contact area in square meters (m²), and temperature difference in kelvin (K). All values must be positive and non-zero.

5. Frequently Asked Questions (FAQ)

Q1: What factors affect thermal contact conductance?
A: Surface roughness, contact pressure, interstitial materials, surface flatness, and thermal properties of the contacting materials.

Q2: What are typical values for h_c?
A: Values range from 100-50,000 W/m²K depending on materials and contact conditions. Metal-to-metal contacts typically range from 1,000-50,000 W/m²K.

Q3: How does surface roughness affect h_c?
A: Increased surface roughness generally decreases h_c due to reduced actual contact area and increased thermal resistance at the interface.

Q4: Can thermal interface materials improve h_c?
A: Yes, thermal greases, pads, and phase change materials can fill air gaps and significantly improve thermal contact conductance.

Q5: What's the difference between h_c and thermal conductivity?
A: Thermal conductivity is a material property, while contact heat transfer coefficient depends on the interface conditions between two materials.