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Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
8th Edition
ISBN: 9781305387102
Author: Kreith, Frank; Manglik, Raj M.
Publisher: Cengage Learning
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
Transcribed Image Text:A radiant-heating system is installed in the plaster ceiling of a room 36 ft long
by 18 ft wide by 9 ft high. Assume direct radiation. The temperature of the
concrete floor is maintained at 75°F. The temperature of the air passing through
the room is held at 75°F. If the required heat supply to the floor is 8000 BTU/hr,
calculate the necessary temperature at the ceiling surface. How much heat is
transferred to the air, in BUT/hr? Emissivity of plaster = 0.93; absorptivity of
concrete = 0.63. The convective heat-transfer coefficient between the ceiling
and the air is given by the equation hc = 0.20 (AT)¹/4.
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- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning
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