An annular aluminium fin (k = 210 W/m.K) is attached to a circular tube having an outside diameter of 25 mm and a surface temperature of 250°C. The fin is 1 mm thick and 10 mm long. The fin is exposed...

An annular aluminium fin (k = 210 W/m.K) is attached to a circular tube having an outside diameter of 25 mm and a surface temperature of 250°C. The fin is 1 mm thick and 10 mm long. The fin is exposed in an ambient at 25°C with h = 25 W/ m².K.

 (a) What is the heat loss from the fin ?

 (b) If 200 such fins are spaced at 5 mm increments along the tube length, what is the heat loss per metre of the tube length ?