Engineering, 26.11.2019 03:31 rubiim9610

Arefrigerator door has a height and width of h = 1 m and w = 0.65 m, respectively, and is situated in a large room for which the air and walls are at t_infinity = t_sur = 25 degree c.
the door consists of a layer of polystyrene insulation (k = 0.03 w/m cdot k) sandwiched between thin sheets of steel (epsilon = 0.6) and polypropylene.
under normal operating conditions, the inner surface of the door is maintained at a fixed temperature of t_s, i = 5 degree c.

a) estimate the heat transfer through the door for the worst-case condition corresponding to no insulation (l = 0).

b) estimate the heat transfer and the outer surface temperaâture for an insulation thickness of l = 15 mm.

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Arefrigerator door has a height and width of h = 1 m and w = 0.65 m, respectively, and is situated i...

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