3-71 A 4-m-high and 6-m-wide wall consists of a long 15-cm x 25-cm cross section of horizontal bricks (k = 0.72 W/m-K) separated by 3-cm-thick plaster layers (k = 0.22 W/m-K). There are also 2-cm-thick plaster layers on each side of the wall, and a 2-cm-thick rigid foam (k = = 0.026 W/m-K) on the inner side of the wall. The indoor and the outdoor temperatures are 22°C and -4°C, and the convection heat transfer coefficients on the inner and the outer sides are h₁ = 10 W/m²·K and h₂ =20 W/m² K, respectively. Assuming one- dimensional heat transfer and disregarding radiation, determine the rate of heat transfer through the wall. Foam Plaster C1.5 cm Brick 25 cm 2 kokk 15 cm 2 1.5 cm

3-71 A 4-m-high and 6-m-wide wall consists of a long 15-cm x 25-cm cross section of horizontal bricks (k = 0.72 W/m-K) separated by 3-cm-thick plaster layers (k = 0.22 W/m-K). There are also 2-cm-thick plaster layers on each side of the wall, and a 2-cm-thick rigid foam (k = = 0.026 W/m-K) on the inner side of the wall. The indoor and the outdoor temperatures are 22°C and -4°C, and the convection heat transfer coefficients on the inner and the outer sides are h₁ = 10 W/m²·K and h₂ =20 W/m² K, respectively. Assuming one- dimensional heat transfer and disregarding radiation, determine the rate of heat transfer through the wall. Foam Plaster C1.5 cm Brick 25 cm 2 kokk 15 cm 2 1.5 cm

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter42: Heat Gains And Heat Losses In Structures

Section: Chapter Questions

Problem 11RQ: If a wall is made up of four different materials, all layered one on top of the other, how will the...

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