Hot air flows with a mass rate of m = 0.060 kg/s through an uninsulated sheet metal duct of diameter D = 0.18 m, which is in the crawlspace of a house. The hot air enters at 120 C and, after a distance of L = 5 m, cools to 80 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. a. Calculate the heat loss (W) from the duct over the length L. h. Determine the heat flux and the duct surface temperature at x= 1.

Hot air flows with a mass rate of m = 0.060 kg/s through an uninsulated sheet metal duct of diameter D = 0.18 m, which is in the crawlspace of a house. The hot air enters at 120 C and, after a distance of L = 5 m, cools to 80 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. a. Calculate the heat loss (W) from the duct over the length L. h. Determine the heat flux and the duct surface temperature at x= 1.

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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