A wall of concrete is 100 mm thick and has an area of 4 m². Its faces are held at 16 °C and -5 °C. Find the heat flux q″ through the wall.
Heat conduction worksheet with answers
A wall of glass is 150 mm thick and has an area of 8 m². Its faces are held at 18 °C and -10 °C. Find the heat flux q″ through the wall.
A wall is made of 150 mm of expanded polystyrene and 25 mm of gypsum board, with an area of 10 m². The outer faces are at 24 °C and 3 °C. Find the heat flow Q̇ through the wall.
A wall is made of 150 mm of gypsum board and 75 mm of expanded polystyrene, with an area of 20 m². The outer faces are at 19 °C and -13 °C. Find the heat flow Q̇ through the wall.
A wall of 100 mm wood and 150 mm gypsum board separates a room at 21 °C from outside air at -10 °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 heat loss Q̇ through the wall.
A wall of 50 mm mineral wool and 75 mm wood separates a room at 21 °C from outside air at -3 °C. The convection coefficients are 10 W/(m²·K) inside and 20 W/(m²·K) outside, and the wall area is 12 m². Find the temperature Ts of the inside surface of the wall.
Answer key
- 1. q″ = 294 W/m²
- 2. q″ = 179.2 W/m²
- 3. Q̇ = 47.37 W
- 4. Q̇ = 211.6 W
- 5. Q̇ = 76.99 W
- 6. Ts = 19.7 °C
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