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Question: do the problem in the green square...

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Do the problem in the green square

3.13 A house has a composite wall of wood, fiberglass insula- tion, and plaster board, as indicated in the sketch. On a cold winter day, the convection heat transfer coefficients are he= 60 W/㎡-K and h, = 30 W/m, K. The total wall surface area is 350 m2 Glass fiber blanket (28 kg/m2), k Plaster board, Plywood siding, k Outside 10 mm →{ -100 mm- H -20mm (a) Determine a symbolic expression for the total thermal resistance of the wall, including inside and outside convection effects for the prescribed conditions. (b) Determine the total heat loss through the wall (c) If the wind were blowing violently, raising h, to 300 W/m2.K, determine the percentage increase in the heat loss. d What is the controlling resistance that determines the the composite wall of Problem 3.13 under con- itions for which the inside air is still characterized by 20°C andh30 W/m K. However, use the realistic conditions for which the outside air is haracterized by a diumal (time) varying temperature of e form 7..AK)-273 + 5 sin( 0sIs12 h K-273+11sin ith h. 60 W/m2.K. Assuming quasi-steady condi- y be neglected, estimate the daily heat loss through 12Sis24 h 24 ons for which changes in energy storage within the wall if its total surface area is 200 m

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