1. A 140 mm thick wall of 5 m x 3 m size is made of red brick (k = 0.6 W/m-K). It is covered on both sides by layers of plaster, 2 cm thick (k = 0.71 W/m-K). The wall has a double pane window size of 120 cm x 120 cm. The double pane window consists of 2 sheets of glass 6 mm thick (k = 0.96 W/m-K) separated by 138.8 mm thick air gap (k = 0.025 W/m- K). If the inner and outer surface temperatures are 18°C and 37°C, determine the total rate of heat transfer (W) through the composite wall and glass window. Express your final answer in five significant figures.

1. A 140 mm thick wall of 5 m x 3 m size is made of red brick (k = 0.6 W/m-K). It is covered on both sides by layers of plaster, 2 cm thick (k = 0.71 W/m-K). The wall has a double pane window size of 120 cm x 120 cm. The double pane window consists of 2 sheets of glass 6 mm thick (k = 0.96 W/m-K) separated by 138.8 mm thick air gap (k = 0.025 W/m- K). If the inner and outer surface temperatures are 18°C and 37°C, determine the total rate of heat transfer (W) through the composite wall and glass window. Express your final answer in five significant figures.

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.39P

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