Net radiative heat transfer
Estimate outward radiative power from a gray surface to large uniform surroundings.
Method and scope
Outward power = ε σ A (T_surface⁴ − T_surroundings⁴), with σ ≈ 5.67 × 10⁻⁸ W/(m² K⁴).
Use net radiative heat transfer for educational calculation or a clearly scoped arithmetic estimate. Intended for Learners, General educational use.
Inputs- Radiating surface area — m², ft²
- Surface emissivity — 1
- Surface temperature — K, °C, °F
- Surroundings temperature — K, °C, °F
Assumptions: Uniform surface temperature and gray emissivity; large isothermal surroundings completely enclose the surface. Absolute temperatures are normalized to kelvin. Positive power means net heat leaving the surface.
Limitations: No convection, conduction, spectral emissivity or finite-surface view factors. The constant is rounded to three significant figures.
Method version 1.0.0 · Unit registry and result provenance are shown after calculation. This tool is limited to the documented scope.Explore related fields
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