Steam passes into tubes in a heating system whose outer diameter is 3 cm and whose wall is held at a temperature of 120°C. Tubes are connected to circular aluminium alloy fins (k = 180 W/m. ° C) with an outer diameter of 6 cm and a constant thickness of 2 mm. The distance between the two fins is 3 mm and the tube length is 200 fins per meter. With h = 60 W/m2.°C, the heat is transmitted to the ambient air at 25°C. Evaluate the increase in heat transfer from the tube per meter of its length as a result of adding fins.

Steam passes into tubes in a heating system whose outer diameter is 3 cm and whose wall is held at a temperature of 120°C. Tubes are connected to circular aluminium alloy fins (k = 180 W/m. ° C) with an outer diameter of 6 cm and a constant thickness of 2 mm. The distance between the two fins is 3 mm and the tube length is 200 fins per meter. With h = 60 W/m2.°C, the heat is transmitted to the ambient air at 25°C. Evaluate the increase in heat transfer from the tube per meter of its length as a result of adding fins.

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 2.60P

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