Square section pin fins with side W= 2 mm and length L = 25 mm are used to enhance heat transfer from a maintained surface at Tb = 150°C. One end of the fin is attached at x = 0, while the other end (x = 25 mm) can be considered insulated. Air flowing between over the fins is also at a temperature, T. = 30°C, and a constant convection coefficient, h = 100 W/m². K is maintained over the entire fin surface. The fin is made of Aluminum having thermal conductivity, k=200 W/m-K. Calculate the following: (a) Single fin (a) The fin parameter, m (b) The fin efficiency, Nm (c) Determine the fin heat transfer rate q in (d) The fin effectiveness & (e) The total rate of heat transfer (qmaul) 150 mm 25 x25 fins from an 150 mm by 150 mm section of the surface having number of fins, N-25 x 25 = 625, (f) The single fin resistance (g) The total fin-array resistance R, of part (e). 150 mm- "armay (b) Fin Array .........

Square section pin fins with side W= 2 mm and length L = 25 mm are used to enhance heat transfer from a maintained surface at Tb = 150°C. One end of the fin is attached at x = 0, while the other end (x = 25 mm) can be considered insulated. Air flowing between over the fins is also at a temperature, T. = 30°C, and a constant convection coefficient, h = 100 W/m². K is maintained over the entire fin surface. The fin is made of Aluminum having thermal conductivity, k=200 W/m-K. Calculate the following: (a) Single fin (a) The fin parameter, m (b) The fin efficiency, Nm (c) Determine the fin heat transfer rate q in (d) The fin effectiveness & (e) The total rate of heat transfer (qmaul) 150 mm 25 x25 fins from an 150 mm by 150 mm section of the surface having number of fins, N-25 x 25 = 625, (f) The single fin resistance (g) The total fin-array resistance R, of part (e). 150 mm- "armay (b) Fin Array .........

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 7.53P

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