A wall of expanded polystyrene is 200 mm thick and has an area of 6 m². Its faces are held at 20 °C and -3 °C. Find the heat flux q″ through the wall.
Heat conduction worksheet with answers
A wall of concrete is 10 mm thick and has an area of 15 m². Its faces are held at 18 °C and -7 °C. Find the rate of heat conduction Q̇ through the wall.
A wall is made of 50 mm of wood and 150 mm of glass, with an area of 6 m². The outer faces are at 17 °C and 3 °C. Find the temperature Ti at the interface between the two layers.
A wall is made of 150 mm of gypsum board and 150 mm of wood, with an area of 8 m². The outer faces are at 22 °C and -10 °C. Find the temperature Ti at the interface between the two layers.
A wall of 150 mm gypsum board and 150 mm wood separates a room at 22 °C from outside air at 4 °C. The convection coefficients are 10 W/(m²·K) inside and 30 W/(m²·K) outside, and the wall area is 6 m². Find the heat loss Q̇ through the wall.
A wall of 250 mm expanded polystyrene and 50 mm gypsum board separates a room at 21 °C from outside air at 2 °C. The convection coefficients are 7.7 W/(m²·K) inside and 30 W/(m²·K) outside, and the wall area is 15 m². Find the heat loss Q̇ through the wall.
Answer key
- 1. q″ = 4.025 W/m²
- 2. Q̇ = 52500 W
- 3. Ti = 7.857 °C
- 4. Ti = 6 °C
- 5. Q̇ = 56.9 W
- 6. Q̇ = 37.5 W
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