17-130 Steam in a heating system flows through tubes whose outer diameter is 3 cm and whose walls are maintained at a temperature of 120°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 Fig. P17-130. The space between the fins is 3 mm, and thus there are 200 fins per meter length of the tube. Heat is transferred to the surround- ing air at 25°C, with a combined heat transfer coefficient of 60 W/m²-K. Determine the increase in heat transfer from the tube per meter of its length as a result of adding fins. r₂ = 3 cm Tb ₁=1.5 cm Too h t = 2 mm S = 3 mm

17-130 Steam in a heating system flows through tubes whose outer diameter is 3 cm and whose walls are maintained at a temperature of 120°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 Fig. P17-130. The space between the fins is 3 mm, and thus there are 200 fins per meter length of the tube. Heat is transferred to the surround- ing air at 25°C, with a combined heat transfer coefficient of 60 W/m²-K. Determine the increase in heat transfer from the tube per meter of its length as a result of adding fins. r₂ = 3 cm Tb ₁=1.5 cm Too h t = 2 mm S = 3 mm

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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