Consider an ice chest with the following dimensions: length= 50 cm, width= 40 cm
ID: 2301954 • Letter: C
Question
Consider an ice chest with the following dimensions:
length= 50 cm, width= 40 cm, and height= 30 cm, made of a 3-cm-thick insulating material (k= 0.033 W/[m *C]). The chest is filled with 30 kg of ice at 0*C. The inner wall surface temperature of the ice chest is assumed to be constant at 0*C. The latent heat of fusion of ice is 333.2 kJ/kg. The outside wall surface temperature of the chest is assumed to remain constant at 25*C.
How long would it take to completely melt the ice? Assume negligible heat transfer through the bottom surface.
Explanation / Answer
in order to completely melt the ice:
the heat required to just melt the ice must be supplied
mL- is the heat required to melt the ice
ka(t2-t1)/thickness of the wall is the heat transferred
30*333.2*1000=0.033*(25/0.03)*((2*0.5*0.3)+(2*0.4*0.3)*(0.5*0.4))*time taken
time taken=136.5h