A non-thermally insulated industrial water vapor pipe is 25 m long and 100 mm in diameter. This line crosses a building whose walls and ambient air are at 25oC. Pressurized steam holds the tube surface at 150oC and the convective coefficient is 10 W/(m.K). The surface emissivity is ε=0.8. (a) the heat loss on this line; (b) if the steam is generated in a boiler that operates at 90% efficiency and uses natural gas priced at $0.20/MJ, what is the annual cost of this heat loss?

A non-thermally insulated industrial water vapor pipe is 25 m long and 100 mm in diameter. This line crosses a building whose walls and ambient air are at 25oC. Pressurized steam holds the tube surface at 150oC and the convective coefficient is 10 W/(m.K). The surface emissivity is ε=0.8. (a) the heat loss on this line; (b) if the steam is generated in a boiler that operates at 90% efficiency and uses natural gas priced at $0.20/MJ, what is the annual cost of this heat loss?

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 7.17P: Determine the rate of heat transfer per meter length to a light oil flowing through a 2.5-cm-ID,...

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