A circumferential fin of rectangular profile is installed on a 10-cm-diameter tube maintained at 120C. The fin

Question:

A circumferential fin of rectangular profile is installed on a 10-cm-diameter tube maintained at 120ºC. The fin has a length of 15 cm and thickness of 2 mm. The fin is exposed to a convection environment at 23ºC with h = 60 W/m2 ∙ ºC and the fin conductivity is 120 W/m ∙ ºC. Calculate the heat lost by the fin expressed in watts.