Radiation Heat Transfer Calculator

Net radiative flux between two surfaces

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Radiation Heat Transfer

Net radiative flux between two surfaces

$$q = \varepsilon \sigma A \left(T_1^4 - T_2^4\right)$$σ = 5.67×10⁻⁸ W/m²·K⁴

Stefan-Boltzmann law. $\varepsilon=1$ for blackbody. T must be in Kelvin. $T^4$ dependence dominates at high temperatures.

ε (0–1)

A (m²)

T₁ (K)

T₂ (K)

All fields required; ε between 0–1.

Radiative Heat Rate q

—W

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