Air at 27°C and a velocity of 5 m/s passes over the small region As (20 mm x 20 mm) on a large surface, which is maintained at Ts = 127°C. For these conditions, 0.5 W is removed from the surface As. In order to increase the heat removal rate, a stainless steel (AISI 304) pin fin of diameter 5 mm is affixed to As, which is assumed to remain at Ts = 127°C.

(a) Determine the maximum possible heat removal rate through the fin.

(b) What fin length would provide a close approximation to the heat rate found in part (a)?

(c) Determine the fin effectiveness, ϵ_f.

(d) What is the percentage increase in the heat rate from As due to installation of the fin?

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- D Air -A, T, A, T, 11t