Home Back

Radiation Heat Transfer Calculator

Radiation Heat Transfer Formula:

\[ Q = \sigma \epsilon A (T_1^4 - T_2^4) \]

K
K
W

Unit Converter ▲

Unit Converter ▼

From: To:

1. What is Radiation Heat Transfer?

Definition: This calculator computes the thermal radiation energy transfer between two surfaces based on the Stefan-Boltzmann law.

Purpose: It helps engineers and physicists determine the radiant heat exchange between objects at different temperatures.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Q = \sigma \epsilon A (T_1^4 - T_2^4) \]

Where:

Explanation: The formula calculates the net radiant energy exchange between two surfaces based on their temperatures and material properties.

3. Importance of Radiation Heat Transfer Calculation

Details: Accurate calculation is crucial for thermal system design, energy efficiency analysis, and temperature control in various applications.

4. Using the Calculator

Tips: Enter the emissivity (0-1), surface area in m², and both temperatures in Kelvin. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is typical emissivity for common materials?
A: Black body = 1, polished metals ≈ 0.05-0.2, oxidized metals ≈ 0.3-0.7, most non-metals ≈ 0.7-0.95.

Q2: Why must temperatures be in Kelvin?
A: The Stefan-Boltzmann law requires absolute temperature (Kelvin) because radiation depends on T⁴.

Q3: What if T₂ > T₁?
A: The result will be negative, indicating heat flows in the opposite direction (from T₂ to T₁).

Q4: Does this account for view factors?
A: No, this is for direct radiation between surfaces. For complex geometries, view factors must be considered.

Q5: What's the Stefan-Boltzmann constant?
A: It's a fundamental physical constant (5.67×10⁻⁸ W/m²K⁴) that appears in the law of thermal radiation.

Radiation Heat Transfer Calculator© - All Rights Reserved 2025