Ql: Consider a copper ( k= 396 W/m K ) long cylindrical fin 0.25 cm in diameter that protrudes from a wall at 95°C into ambient air at 25°C. The heat transfer is mainly by natural convection with a coefficient equal to 10 W/m2 K. Calculate the heat loss, assuming that (a) the fin is very long and (b) the fin is an infinite length of 2.5 cm. (c) calculate fin efficency for case b.

Ql: Consider a copper ( k= 396 W/m K ) long cylindrical fin 0.25 cm in diameter that protrudes from a wall at 95°C into ambient air at 25°C. The heat transfer is mainly by natural convection with a coefficient equal to 10 W/m2 K. Calculate the heat loss, assuming that (a) the fin is very long and (b) the fin is an infinite length of 2.5 cm. (c) calculate fin efficency for case b.

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.18P

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