4. Freezing Boundary Fronts Consider melting of a semi-infinite (0 ≤ x < ∞) slab of paraffin (octadecane), initially at the melting temperature Tinitial = Tmelt = 28.6°C exposed to a temperature Th = 60°C at x = 0. Find (a) The front location after 1 hour (b) The front location after 2 hours (c) The time for the melting front to reach 5 cm (d) The temperature at x = 1 cm after 2 hours. (Use k = 0.23 W/mK, Cp = 2500 J/kgK, AH = 250 kJ/kg, p= 800 kg/m 3 ) III E

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