An annular stainless steel (k = 16.6 W/m * K) fin of thickness 5 mm and outside diameter 3 cm is attached to a 1-cm OD tube. The fin is surrounded by a fluid at 50 C with a heat-transfer coefficient of 40 W/m2 * K. The tube wall temperature is 150 C. Calculate:(a) The fin efficiency.(b) The rate of heat transfer from the fin. Ans. (a) 91%. (b) 6.4 W.

A substance (A) reacts to form another substance (B) according to: 3B(g) = 2A(g) The reaction is run at a particular temperature with the concentrations of A and B monitored over time and plotted on the graph below. At what time was equilibrium fırst reached and what is the approximate value of the equilibrium constant? 2.0 1.8 E 1.6 1.4 [B] 1.2 1.0 0.8 0.6 0.4 [A] 0.2 0.0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 time / min O Equilibrium was reached at 70 min with K. = 0.0056. O Equilibrium was reached at 30 min with K. = 0.0056. Equilibrium was reached at 30 min with K. = 0.023. Equilibrium was reached at 70 min with K. = 0.023. concentration / M

D -A₂ = Ac Obtain a relation for the fin efficiency for a fin of constant cross-sectional area Ac, perimeter p, length L, and thermal conductivity k exposed to convection to a medium at T with a heat transfer coefficient h. Assume the fins are sufficiently long so that the temperature of the fin at the tip is nearly T... Take the temperature of the fin at the base to be Tb and neglect heat transfer from the fin tips. Simplify the relation for (a) a circular fin of diameter D and (b) rectangular fins of thickness t. h, T

A rectangular fin 1.0 ft long, 1.0 ft wide, and 2in. thick loses heat to the atmosphere at70 F. The base of the fin is at 270 F.If h = 2Btu/h*ft2* F and the thermal conductivity of the fin is 24Btu/h*ft* F, find:(a) The fin efficiency.(b) The total rate of heat loss from the fin.Ans. (a) 70.5%. (b) 712 Btu/h.

Q: water at 200² flows over 90.3m square Plate at velocity of 6 m/s at constant Plate is maintained Temperature at 556° calclate the heat by the plate. heat Transfer