Radiated energy flux

Input(s)

c: Speed of Light $(\mathrm{ft} / \mathrm{s})$

$\mathrm{h}$: Planck's Constant $\left(\mathrm{lb} \mathrm{ft}^{2} / \mathrm{s}\right)$

$\lambda$: Wavelength (ft)

$\mathrm{k}$: Stefan-Boltzmann Constant $\left(\mathrm{BTU} / \mathrm{h} \mathrm{ft}^{2}{ }^{\circ} \mathrm{R}^{4}\right)$

T: Temperature $(\mathrm{K})$

Output(s)

q: Radiated Energy Flux from a Black Surface in the Wavelength Range $\left(B T U / \mathrm{ft}^{2} \mathrm{~s}^{3}\right)$

Formula(s)

$$ \mathrm{q}=\frac{2 * \pi *\left(\mathrm{c}^{2}\right) * \mathrm{~h}}{\left(\lambda^{5}\right) *\left(\exp \left(\frac{\mathrm{c} * \mathrm{~h}}{\lambda * \mathrm{k} * \mathrm{~T}}\right)-1\right)} $$

Reference(s)

Bird, R.B., Stewart, W.E. and Lightfoot, E.N. (2002). Transport Phenomena (Second Ed.). John Wiley \& Sons, Chapter: 16, Page: 494.