Reconsider Prob. 3–67. Using EES (or other) software, plot the rate of heat transfer through the wall as a function of the thickness of the rigid foam in the range of 1 cm to 10 cm. Discuss the results.

Data from problem 67

A 4-m-high and 6-m-wide wall consists of a long 18-cm × 30-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-cmthick 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 24°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.

Transcribed Image Text:

Foam - Plaster Brick 18 cm 1.5 cm 30 cm 1.5 cm