Stefan-Boltzmann law

Input(s)

$\sigma$: Stefan Boltzmann Constant (1.713 E-9) $\left(\mathrm{BTU} / \mathrm{ft}^{2} \mathrm{~h}^{\circ} \mathrm{R}^{4}\right)$

$T$: Temperature $\left({ }^{\circ} \mathrm{F}\right)$

$\varepsilon$: Emissivity (fraction)

Output(s)

$u_{i}$: Rate of Radiation Heat Transfer Per Unit Area $\left(\mathrm{BTU} / \mathrm{h} \mathrm{ft}^{2}\right.$ )

Formula(s)

$$ \mathrm{u}_{\mathrm{i}}=\sigma * \varepsilon *(\mathrm{~T}+460)^{4} $$

Reference(s)

Pratts, M. (1986). Thermal Recovery Monograph Vol. 7. Society of Petroleum Engineers, Houston, Page: 19.