Consider a large plane wall of thickness L 0 8 ft and thermal conductivity k 1 2 Btu h ft F The wall is covered with a material that has an emissivity of 0 80 and a solar absorptivity of a 0 60 The inner surface of the wall is maintained at T 1 520 R at all times, while the outer surface is exposed...

Assumptions The wall is large and plane so there is no heat transfer in the lateral directions The thermal conductivity of the wall is constant The wa ...

Consider a large plane wall of thickness L = 0.8 ft and thermal conductivity k = 1.2

Question:

Consider a large plane wall of thickness L = 0.8 ft and thermal conductivity k = 1.2 Btu/h · ft · °F. The wall is covered with a material that has an emissivity of ε = 0.80 and a solar absorptivity of a = 0.60. The inner surface of the wall is maintained at T₁ = 520 R at all times, while the outer surface is exposed to solar radiation that is incident at a rate of q̇_solar = 300 Btu/h · ft². The outer surface is also losing heat by radiation to deep space at 0 K. Determine the temperature of the outer surface of the wall and the rate of heat transfer through the wall when steady operating conditions are reached.