In: Mechanical Engineering
A Styrofoam(k = 0.035 W/m-°C) box has outer dimensions of 250 mm x 450 mm x 600 mm and is 3 cm thick. Initially, the box is filled with 40kg of ice at 0°C, and the inner surface temperature of the ice chest can always be taken to be 0°C. The heat transfer coefficient between the outer surface of box and surrounding air at 35°C is 20 W/m2 -°C. (a) Determine how long it will take for the ice in the box to melt completely. Assume that the heat transfer from the 450 mm x 600 mm bottom of the box is negligible.