Question

A composite wall consists of a 20 mm thick steel plate followed by an insulation brick (k = 0.39 W/mK) of 50 cm thickness and overlaid by glass wool of 20 cm thickness (k = 0.05 W/mK) and a 70 cm layer of brick (k = 0.39 W/mK). The inner wall is exposed to convection at 650°C with h = 65 W/m²K, and the outside is air at 35°C with a convection coefficient of 15 W/m²K. Determine the heat loss per unit area of the wall and the interface temperatures between the walls.

Name: a composite wall consists of a 20 mm thick steel plate followed by an insulation brick k 039 wmk of 50 cm thickness and overlaid by glass wool of 20 cm thickness k 005 wmk and a 70 cm layer 58821
Uploaded: 2022-08-28T15:09:33-08:00
Duration: 5 min 21 s
Channel: Adi S
Description: a composite wall consists of a 20 mm thick steel plate followed by an insulation brick k 039 wmk of 50 cm thickness and overlaid by glass wool of 20 cm thickness k 005 wmk and a 70 cm layer 58821

          A composite wall consists of a 20 mm thick steel plate followed by an insulation brick (k = 0.39 W/mK) of 50 cm thickness and overlaid by glass wool of 20 cm thickness (k = 0.05 W/mK) and a 70 cm layer of brick (k = 0.39 W/mK). The inner wall is exposed to convection at 650°C with h = 65 W/m²K, and the outside is air at 35°C with a convection coefficient of 15 W/m²K. Determine the heat loss per unit area of the wall and the interface temperatures between the walls.

Added by Dawn S.

University Physics with Modern Physics

Hugh D. Young 14th Edition

Instant Answer

Solved by Expert Adi S

08/28/2022

Step 1

Given resistances: - \(R_1 = \frac{1}{h} = \frac{1}{65} = 0.015384 \, \text{m}^2\cdot\text{K}/\text{W}\) - \(R_2 = \frac{0.02}{14} = 1.4286 \times 10^{-3} \, \text{m}^2\cdot\text{K}/\text{W}\) - \(R_3 = \frac{0.5}{0.39} = 1.282 \, Show more…

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A composite wall consists of a 20 mm thick steel plate followed by an insulation brick (k = 0.39 W/mK) of 50 cm thickness and overlaid by glass wool of 20 cm thickness (k = 0.05 W/mK) and a 70 cm layer of brick (k = 0.39 W/mK). The inner wall is exposed to convection at 650°C with h = 65 W/m²K, and the outside is air at 35°C with a convection coefficient of 15 W/m²K. Determine the heat loss per unit area of the wall and the interface temperatures between the walls.