A wall of gypsum board is 20 mm thick and has an area of 12 m². Its faces are held at 23 °C and 1 °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 6 m². Its faces are held at 23 °C and 5 °C. Find the rate of heat conduction Q̇ through the wall.
A wall is made of 200 mm of wood and 100 mm of gypsum board, with an area of 20 m². The outer faces are at 22 °C and -1 °C. Find the heat flow Q̇ through the wall.
A wall is made of 100 mm of gypsum board and 100 mm of wood, with an area of 6 m². The outer faces are at 19 °C and 4 °C. Find the temperature Ti at the interface between the two layers.
A wall of 200 mm mineral wool and 25 mm concrete separates a room at 22 °C from outside air at -9 °C. The convection coefficients are 6 W/(m²·K) inside and 25 W/(m²·K) outside, and the wall area is 8 m². Find the temperature Ts of the inside surface of the wall.
A wall of 250 mm brick and 75 mm glass separates a room at 21 °C from outside air at 2 °C. The convection coefficients are 7.7 W/(m²·K) inside and 20 W/(m²·K) outside, and the wall area is 8 m². Find the overall heat transfer coefficient U of the wall.
Answer key
- 1. q″ = 187 W/m²
- 2. Q̇ = 15120 W
- 3. Q̇ = 260.7 W
- 4. Ti = 11.5 °C
- 5. Ts = 21.01 °C
- 6. U = 1.652 W/(m²·K)
Full step-by-step solutions: practise this topic on examproblems.com.