Consider the radiation heat transfer from an open fireplace that has a fire in it, as shown in the figure. The effective surface temperature of the fire is 600ºF and the fire has an effective emissivity of 0.95. The surroundings act as a black body at 60ºF. Determine the net heat transfer to a person sitting in front of the fireplace and the equilibrium surface temperature facing the fireplace. Neglect radiation from the back side and assume a shape factor of 0.15 for the opening of the fireplace to the person.
The equivalent circuit for heat transfer from the fireplace to the sitting person is
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Fill in the blank(s) with correct word
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