Problem.
The wall of a refrigerator is constructed of fiberglass insulation
sandwiched between two layers of sheet metal. The minimum thickness of
insulation that needs to be used in the wall in order to avoid
condensation on the outer surface to be determined.
Given that
Thermal conductivity for sheet metal = 15.5 W/m 0C
Thermal conductivity for fiberglass insulation = 0.035 W/m 0C
Take Room temperature = 250C
Surrounding Temperature = 20 0C
Temperature in refrigerator = 30C
Heat transfer coefficient h = 9 W/m2 0C
