400 circumferential fins of rectangular profile (k = 386 W/m °C) are installed on a tube having a diameter of 3 cm and 1 m length that is maintained at a temperature of 200°C. The single fin has a length of 2 cm and a thickness of 0.7 mm. The heat is transferred to the surrounding air at 100°C with a convection heat-transfer coefficient of 524 W/m2 °C. How many times is the heat transfer rate enhanced when the fins are installed on the tube?

400 circumferential fins of rectangular profile (k = 386 W/m °C) are installed on a tube having a diameter of 3 cm and 1 m length that is maintained at a temperature of 200°C. The single fin has a length of 2 cm and a thickness of 0.7 mm. The heat is transferred to the surrounding air at 100°C with a convection heat-transfer coefficient of 524 W/m2 °C. How many times is the heat transfer rate enhanced when the fins are installed on the tube?

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.36P

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