To increase the heat dissipation from a 2.5-cm-OD tube, circumferential fins made of aluminum (k=200 W/m K) are soldered to the outer surface. The fins are 0.1 cm thick and have an outer diameter of 5.5 cm as shown in the figure If the tube temperature is 100C, the environmental temperature is 25C, and the heat transfer coefficient between the fins and the environment is 65 W/mK, calculate the rate of heat loss from a fin. Fin efficiency, nf (%) 10 100 5.5 cm 0.1 cm T=25C 2.5cm Tube Fin T = 100C 90 90 80 Straight fin- 70 50 40 40 30 30 0 0.2 0.4 0.6 0.8 1.0 | (ro + ^/^) /r/= | 1.25.50 2.00 3.00. 1.2 1.4 1.6 1.8 2.0 2.2 2.4 3/2 (ro+ -r) 2/k(ro-r) or (L+) 2h/kil Efficiency of circumferential rectangular fins.