A surface has a total hemispherical absorptivity of 0.76 and a total hemispherical emissivity of 0.8. When it is at 500 K and receives an irradiation of 5000 W/m^2, what is the net heat flux to the surface?
Explanation
This quantitative question from Example 12.7 requires performing a surface energy balance to find the net heat flux, which is the difference between the total absorbed irradiation and the total emitted radiation.
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