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)

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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