The addition of aluminum fins has been suggested to increase the rate of heat dissipation from one side of an electronic device 1m wide and 1 m tall. The fins are to be rectangular in cross section, 2.5 cm long and 0.25 cm thick, as shown in the figure. There are to be 100 fins per meter. The convection heat transfer coefficient, both for the wall and the fins, is estimated to be 35 W/m² K. With this infor- mation determine the percent increase in the rate of heat transfer of the finned wall compared to the bare wall.

The addition of aluminum fins has been suggested to increase the rate of heat dissipation from one side of an electronic device 1m wide and 1 m tall. The fins are to be rectangular in cross section, 2.5 cm long and 0.25 cm thick, as shown in the figure. There are to be 100 fins per meter. The convection heat transfer coefficient, both for the wall and the fins, is estimated to be 35 W/m² K. With this infor- mation determine the percent increase in the rate of heat transfer of the finned wall compared to the bare wall.

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 2.42P: 2.42 A circumferential fin of rectangular cross section, 3.7-cm OD and 0.3 cm thick, surrounds a...

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