3. As shown in Figure, steam in a heating system flows through tubes whose outer diameter is 5 cm and whose walls are maintained at a 2.5 cm 3 cm temperature of 180°C. Circular aluminum alloy 2024-T6 fins (k= 186 W/m-°C) of outer diameter 6 cm and constant thickness 1 mm are attached to the tube. The space between the fins is 3 mm, and thus there are 250 fins per meter length of the tube. Heat is transferred to the surrounding air at To = 25°C, with a heat transfer coefficient of 40 W/m2.°C. Determine the increase in heat transfer from the tube T. = 25°C 180°C 1 mm 3 mm per meter of its length because of adding fins, including overall fin effectiveness. (Answers: 2639 W, 3.71)

3. As shown in Figure, steam in a heating system flows through tubes whose outer diameter is 5 cm and whose walls are maintained at a 2.5 cm 3 cm temperature of 180°C. Circular aluminum alloy 2024-T6 fins (k= 186 W/m-°C) of outer diameter 6 cm and constant thickness 1 mm are attached to the tube. The space between the fins is 3 mm, and thus there are 250 fins per meter length of the tube. Heat is transferred to the surrounding air at To = 25°C, with a heat transfer coefficient of 40 W/m2.°C. Determine the increase in heat transfer from the tube T. = 25°C 180°C 1 mm 3 mm per meter of its length because of adding fins, including overall fin effectiveness. (Answers: 2639 W, 3.71)

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 7.4P

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