2) A cylinder is constructed of brass material (k-109 W/m K) and is of height H-65...

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2) A cylinder is constructed of brass material (k-109 W/m K) and is of height H-65 mm and outside diameter D-50 mm. Under typical operating conditions the outer surface of the cylinder is at T 370 K and is exposed to ambient air at T.= 300 K with a convection coefficient of h=30 W/mK. Annular fins are integrally cast with the cylinder to increase heat transfer to the surroundings. Consider 6 fins, which are of thickness 1-5 mm. length L-25 mm and equally spaced. Neglecting the contact surface resistance, radiation and assuming steady-state one-dimensional heat transfer; Calculate the fin area (Ar) and total area (A.), (10 pts) a) b) Find the fin efficiency (nr). (20 pts) c) Determine the total rate of heat transfer from the fins and the base (unfinned) surface (q). (20 pts) H = 65 mm " = 25 mm L = 25 mm T = 50 mm 11-5 mm T-370 K Figure 1: Scheme for Question 2 T = 300 K h=30 W/mK ||| Air 2) A cylinder is constructed of brass material (k-109 W/m K) and is of height H-65 mm and outside diameter D-50 mm. Under typical operating conditions the outer surface of the cylinder is at T 370 K and is exposed to ambient air at T.= 300 K with a convection coefficient of h=30 W/mK. Annular fins are integrally cast with the cylinder to increase heat transfer to the surroundings. Consider 6 fins, which are of thickness 1-5 mm. length L-25 mm and equally spaced. Neglecting the contact surface resistance, radiation and assuming steady-state one-dimensional heat transfer; Calculate the fin area (Ar) and total area (A.), (10 pts) a) b) Find the fin efficiency (nr). (20 pts) c) Determine the total rate of heat transfer from the fins and the base (unfinned) surface (q). (20 pts) H = 65 mm " = 25 mm L = 25 mm T = 50 mm 11-5 mm T-370 K Figure 1: Scheme for Question 2 T = 300 K h=30 W/mK ||| Air