Delow. The 8uter surfaces are exposed to a fluid at 25°C and a convection heat transfer coefficient of 1000 W/m2.K. The middle wall B experiences uniform heat generation dg, while there is no generation in walls A and C. The temperatures at the interfaces are T1 261°C and T2 211°C. Assuming negligible contact resistance at the interfaces: A) Determine the outside surface temperature of walls A and C? B) Compute the value of d;? 111 !!! kA = 25 W/m-K ke = 50 W/m-K (7 M) LA = 30 mm La = 30 mm L = 20 mm !3! !! Q2: The engine cylinder of a motorcycle is constructed of 2024-T6 aluminum alloy (k-186 W/m.K) and is of height H-0.15 m and outside diameter D-50 mm. Under typical operating conditions the outer surface of the cylinder is at a temperature of 500 K and is exposed to ambient air at 300 K, with a convection coefficient of 50 W/m2.K. Annular fins are integrally cast with the cylinder to increase heat transfer to the surroundings. Consider five such fins, which are of thickness t=6 mm, length L=20 mm, and equally spaced. What is the increase in heat transfer due to use of the fins? (8 M) Engine cylinder cross section (2024 T6 Al alloy) N 00s = "L T 300 K h= 50 WimK H= 0.15 m ww 9 =1 wu s2 = L= 20 mm 45 mm to arr Ini the apples are at a uniform temperature of 20 °C, and the heat transfer coefficient on be p 840 kg/m', Cp 3.81 kJ/kg C, k 0.418 W/m °C, and a 1.3x107 m/s, determine the center and tem of the apples after lhour. Also, determine the amount of heat transfer from the surfaces is 8 W/m? .°C. Treating the apples as 9 cm diameter spheres and taking their properties to %3D each apple. (5 M) Good Luck