A short brass cylinder (ρ = 8530 kg/m³, c_p= 0.389 kJ/kg·K, k = 110 W/m·K, and α = 3.39 × 10^-5m²/s) of diameter 8 cm and height 15 cm is initially at a uniform temperature of 150°C. The cylinder is now placed in atmospheric air at 20°C, where heat transfer takes place by convection with a heat transfer coefficient of 40 W/m²·K. Calculate

(a) The center temperature of the cylinder;

(b) The center temperature of the top surface of the cylinder;

(c) The total heat transfer from the cylinder 15 min after the start of the cooling.

Transcribed Image Text:

Ambient air Brass cylinder 20°C 15 cm -8 cm- 150°C