bb) Hot air at 60 °C leaving the furnace of a house enters a 12 m long section of a sheetmetal duct of rectangular cross section 20 cm x 20 cm at an average velocity of4 m/s. The thermal resistance of the duct is negligible, and the outer surface of theduct, whose emissivity is 0.3, is exposed to the cold air at 10 °C in the basement,with a convection heat transfer coeffbasement to be at 10 °C also, detleave the basemeņt and 6) the rate of heat loss from the hot air in the duct to thebasement. (2622 W, 45.1 C)y of 10 W/m².°C. Taking the walls of theine (a) the temperature at which the hot air willHma

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bb) Hot air at 60 °C leaving the furnace of a house enters a 12 m long section of a sheet metal duct of rectangular cross section 20 cmx 20 cm at an average velocity of 4 m/s. The thermal resistance of the duct is negligible, and the outer surface of the duct, whose emissivity is 0.3, is with a convection heat transfer coe o the cold air at 10 °C in the basement, of 10 W/m2.°C. Taking the walls of the basement to be at 10 °C also, determine (a) the temperature at which the hot air will leave the basement and 6) the rate of heat loss from the hot air in the duct to the basement. (2622 W 45.1G)

bb) Hot air at 60 °C leaving the furnace of a house enters a 12 m long section of a sheet metal duct of rectangular cross section 20 cmx 20 cm at an average velocity of 4 m/s. The thermal resistance of the duct is negligible, and the outer surface of the duct, whose emissivity is 0.3, is with a convection heat transfer coe o the cold air at 10 °C in the basement, of 10 W/m2.°C. Taking the walls of the basement to be at 10 °C also, determine (a) the temperature at which the hot air will leave the basement and 6) the rate of heat loss from the hot air in the duct to the basement. (2622 W 45.1G)

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.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.62P

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