A house has a composite wall of plywood, fiberglass insulation, and plaster board, as indicated in Fig. On acold winter day the convection heat transfer coefficients are ho- 60 W/m?K and h= 30 W/m².K. The totalwall surface area is 350 m . If Kp= 0.17 W/m.K, K = 0.036 W/m.K, and K; = 0.12 W/m.K.Glass fiber blanket(28 kg/m), k,Plaster board, k,- Plywood siding, k,InsideOutsideh, T- 20°Ch. T =-15°C1111110 mm +100 mm+ 20 mmA.What are the main assumptions?B.Draw the thermal circuit representing conduction through the composite wall ?C. Drive an expression in symbol form for the total thermal resistance of the composite wall, includinginside and outside convection effects for the prescribed conditions.D.Determine he total heat rate through the wall.E. What is the controlling resistance that determines the heat rate through the wall?

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Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.45P

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