An electric heating system is installed in the ceiling of a room 5 m (length), 5 m (width) and 2.5 m (height). The temperature of the ceiling is 315 K whereas under equilibrium conditions the walls are at 295 K. If the floor is non-sensitive to radiations and the emissivities of the ceiling and wall are 0.75 and 0.65 respectively. Calculate the radiant heat loss from the ceiling to the walls?

An electric heating system is installed in the ceiling of a room 5 m (length), 5 m (width) and 2.5 m (height). The temperature of the ceiling is 315 K whereas under equilibrium conditions the walls are at 295 K. If the floor is non-sensitive to radiations and the emissivities of the ceiling and wall are 0.75 and 0.65 respectively. Calculate the radiant heat loss from the ceiling to the walls?

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.51P

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An electric heating system is installed in the ceiling of a room 5 m (length) × 5 m (width) ×2.5 m (height). The temperature of the ceiling is 315 K whereas under equilibrium conditions the walls are at 295 K. If the floor is non-sensitive to radiations and the emissivities of the ceiling and wall are 0.75 and 0.65, respectively. Calculate the radiant heat loss from the ceiling to the walls. The answer should be 1595 W. Please show steps in your solution
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