A wall of wood is 250 mm thick and has an area of 6 m². Its faces are held at 23 °C and -3 °C. Find the heat flux q″ through the wall.
Heat conduction worksheet with answers
A wall of brick is 200 mm thick and has an area of 20 m². Its faces are held at 23 °C and 8 °C. Find the rate of heat conduction Q̇ through the wall.
A wall is made of 100 mm of mineral wool and 150 mm of wood, with an area of 20 m². The outer faces are at 24 °C and 9 °C. Find the temperature Ti at the interface between the two layers.
A wall is made of 50 mm of brick and 100 mm of concrete, with an area of 8 m². The outer faces are at 19 °C and 9 °C. Find the temperature Ti at the interface between the two layers.
A wall of 100 mm gypsum board and 75 mm brick separates a room at 20 °C from outside air at -8 °C. The convection coefficients are 10 W/(m²·K) inside and 25 W/(m²·K) outside, and the wall area is 6 m². Find the heat loss Q̇ through the wall.
A wall of 250 mm gypsum board and 25 mm concrete separates a room at 20 °C from outside air at -11 °C. The convection coefficients are 8 W/(m²·K) inside and 30 W/(m²·K) outside, and the wall area is 20 m². Find the heat loss Q̇ through the wall.
Answer key
- 1. q″ = 17.68 W/m²
- 2. Q̇ = 1080 W
- 3. Ti = 12.91 °C
- 4. Ti = 14.07 °C
- 5. Q̇ = 201.8 W
- 6. Q̇ = 376.5 W
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