Steam in a heating system flows through tubes whose outer diameter is 3 cm and whose walls are maintained ot a temperature of 121'C. Circular aluminum alloy fins (k = 180 W/m-K) of outer diameter 6 cm and constant thickness t=2 mm are attached to the tube, as shown in the figure. The space between the fins is 3 mm. Thus, there are 200 fins per meter length of the tube. Heat is transferred to the surrounding air at 25°C, with a combined heat transfer coefficient of 60 W/m K. Determine the increase in heat transfer from the tube per meter length as a result of the attached fins. Efficiency of these circular fins is given to be 0.96. 3 cm 1=2 mm S=3 mm The increase in heat transfer is 3912 W.

Steam in a heating system flows through tubes whose outer diameter is 3 cm and whose walls are maintained ot a temperature of 121'C. Circular aluminum alloy fins (k = 180 W/m-K) of outer diameter 6 cm and constant thickness t=2 mm are attached to the tube, as shown in the figure. The space between the fins is 3 mm. Thus, there are 200 fins per meter length of the tube. Heat is transferred to the surrounding air at 25°C, with a combined heat transfer coefficient of 60 W/m K. Determine the increase in heat transfer from the tube per meter length as a result of the attached fins. Efficiency of these circular fins is given to be 0.96. 3 cm 1=2 mm S=3 mm The increase in heat transfer is 3912 W.

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.56P

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