- #1

yellowbird321

- 19

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Hi!

Basically I have some tasks in thermodynamics calculating the heat transfer through a wall.

I have been attempting to solve the following problem:

“Calculate the heat transfer through the exterior wall in a building, where the temperature inside the building is 20 °C and the temperature outside the building is 5 °C. The wall is concrete, and is 4 m high and 8 m long, and have a thickness of 200 mm. The thermal conductivity for the concrete wall is 0,40 W/(mK), the coefficient of heat transfer at the wall inside is 1,2 W/(m2K) and the coefficient of heat transfer at the wall outside is 1,9 W/(m2K).”

I have attempted the following:

q = (k / s) A dT

= U A dT

= [(0,40 W/(mK) / (0.2 m)] [(4 m) (8 m)] [(20 °C) - (5 °C)]

I'm not sure where to begin and what to add into the calculations. The two coefficient of heat transfer confuses me. How do I solve this?

Help is appreciated, thanks.

Basically I have some tasks in thermodynamics calculating the heat transfer through a wall.

I have been attempting to solve the following problem:

“Calculate the heat transfer through the exterior wall in a building, where the temperature inside the building is 20 °C and the temperature outside the building is 5 °C. The wall is concrete, and is 4 m high and 8 m long, and have a thickness of 200 mm. The thermal conductivity for the concrete wall is 0,40 W/(mK), the coefficient of heat transfer at the wall inside is 1,2 W/(m2K) and the coefficient of heat transfer at the wall outside is 1,9 W/(m2K).”

I have attempted the following:

q = (k / s) A dT

= U A dT

= [(0,40 W/(mK) / (0.2 m)] [(4 m) (8 m)] [(20 °C) - (5 °C)]

I'm not sure where to begin and what to add into the calculations. The two coefficient of heat transfer confuses me. How do I solve this?

Help is appreciated, thanks.

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