A wall of concrete is 10 mm thick and has an area of 4 m². Its faces are held at 23 °C and -15 °C. Find the heat flux q″ through the wall.
Heat conduction worksheet with answers
A wall of mineral wool is 10 mm thick and has an area of 12 m². Its faces are held at 24 °C and -15 °C. Find the heat flux q″ through the wall.
A wall is made of 200 mm of gypsum board and 150 mm of concrete, with an area of 4 m². The outer faces are at 22 °C and 2 °C. Find the heat flow Q̇ through the wall.
A wall is made of 100 mm of wood and 50 mm of brick, with an area of 8 m². The outer faces are at 19 °C and -10 °C. Find the heat flow Q̇ through the wall.
A wall of 100 mm gypsum board and 150 mm mineral wool separates a room at 21 °C from outside air at -5 °C. The convection coefficients are 6 W/(m²·K) inside and 20 W/(m²·K) outside, and the wall area is 20 m². Find the overall heat transfer coefficient U of the wall.
A wall of 200 mm concrete and 25 mm wood separates a room at 20 °C from outside air at -14 °C. The convection coefficients are 10 W/(m²·K) inside and 25 W/(m²·K) outside, and the wall area is 4 m². Find the temperature Ts of the inside surface of the wall.
Answer key
- 1. q″ = 5320 W/m²
- 2. q″ = 156 W/m²
- 3. Q̇ = 62.32 W
- 4. Q̇ = 352.8 W
- 5. U = 0.2195 W/(m²·K)
- 6. Ts = 12.09 °C
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