Thermal Radiation
Estimate radiation exchange with large surrounding surfaces.
Your numbers
Net outward radiation
Gray diffuse surface in a large isothermal enclosure, view factor 1; convection and conduction excluded.
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Formula
Use P = εσA(T⁴−Tₛ⁴). ε is emissivity, σ is the Stefan–Boltzmann constant, A is area in m², and T and Tₛ are surface and surrounding temperatures in K. Positive P means net outward power in W.
Estimate radiation exchange with large surrounding surfaces.
Worked example
- Surface emissivity
- 0.9
- Area (m²)
- 1
- Surface absolute temperature (K)
- 400
- Surrounding absolute temperature (K)
- 300
- Net outward radiation
- 893.083970993 W
Scope and limitations
Gray diffuse surface in a large isothermal enclosure, view factor 1; convection and conduction excluded.
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Formula version: 4862487bba0c · Example checked: