Hot air flows with a mass rate of m = 0.050 kg/s through an uninsulated sheet metal duct of diameter D = 0.15 m, which is in the crawlspace of a house. The hot air enters at 103°C and, after a distance of L = 5 m, cool to 77°C. The heat transfer coefficient between the duct outer surface and the ambient air at T, = 0°C is known to be ho = 6 W /m² · K. 1) Calculate the heat loss from the duct over the length L. 2) Determine the heat flux and the duct surface temperature at x=L, assuming fully developed conditions at x = L.

Hot air flows with a mass rate of m = 0.050 kg/s through an uninsulated sheet metal duct of diameter D = 0.15 m, which is in the crawlspace of a house. The hot air enters at 103°C and, after a distance of L = 5 m, cool to 77°C. The heat transfer coefficient between the duct outer surface and the ambient air at T, = 0°C is known to be ho = 6 W /m² · K. 1) Calculate the heat loss from the duct over the length L. 2) Determine the heat flux and the duct surface temperature at x=L, assuming fully developed conditions at x = L.

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.27P

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