A wall of gypsum board is 150 mm thick and has an area of 8 m². Its faces are held at 18 °C and -9 °C. Find the heat flux q″ through the wall.
Heat conduction worksheet with answers
A wall of gypsum board is 20 mm thick and has an area of 20 m². Its faces are held at 24 °C and 8 °C. Find the rate of heat conduction Q̇ through the wall.
A wall is made of 200 mm of glass and 100 mm of expanded polystyrene, with an area of 4 m². The outer faces are at 24 °C and -2 °C. Find the heat flow Q̇ through the wall.
A wall is made of 150 mm of expanded polystyrene and 25 mm of gypsum board, with an area of 15 m². The outer faces are at 20 °C and -15 °C. Find the temperature Ti at the interface between the two layers.
A wall of 250 mm brick and 150 mm wood separates a room at 21 °C from outside air at -3 °C. The convection coefficients are 6 W/(m²·K) inside and 25 W/(m²·K) outside, and the wall area is 15 m². Find the temperature Ts of the inside surface of the wall.
A wall of 250 mm mineral wool and 25 mm glass separates a room at 20 °C from outside air at 0 °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.
Answer key
- 1. q″ = 30.6 W/m²
- 2. Q̇ = 2720 W
- 3. Q̇ = 33.93 W
- 4. Ti = −13.84 °C
- 5. Ts = 18.21 °C
- 6. Q̇ = 18.7 W
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