A meat processing industry has a cold room for handling products whose outer wall is coated with a thermal insulating material. Users have observed that vapor diffusion occurs through the wall and that the water vapor that diffuses condenses when it reaches the inner surface of the insulation layer, which can cause its rapid degradation. Under current conditions, the ambient air inside the room is maintained at an average temperature of 5 °C with a relative humidity of 60%. The insulated wall is 3 m high and 2 m wide, its thickness is 12 mm. The following information is also known: - the solubility of water vapor in the wall material is equal to approximately 0.007 kmol/m3.bar. - the water vapor diffusion coefficient on the wall is equal to 0.2 x10-9 m2/s; - At the inner wall-insulation interface, the water vapor pressure can be considered negligible, since the moisture rapidly condenses upon reaching its surface. (a)- What is the estimate of the vapor diffusion rate on the wall (in g/day), for the current operating conditions; (b)- Quantitatively evaluate the effect of an increase in temperature inside the cold room in the diffusion rate
A meat processing industry has a cold room for handling products whose outer wall is coated with a thermal insulating material. Users have observed that vapor diffusion occurs through the wall and that the water vapor that diffuses condenses when it reaches the inner surface of the insulation layer, which can cause its rapid degradation.
Under current conditions, the ambient air inside the room is maintained at an average temperature of 5 °C with a relative humidity of 60%. The insulated wall is 3 m high and 2 m wide, its thickness is 12 mm.
The following information is also known:
- the solubility of water vapor in the wall material is equal to
approximately 0.007 kmol/m3.bar.
- the water vapor diffusion coefficient on the wall is equal to 0.2 x10-9 m2/s;
- At the inner wall-insulation interface, the water vapor pressure can be considered negligible, since the moisture rapidly condenses upon reaching its surface.
(a)- What is the estimate of the vapor diffusion rate on the wall (in g/day), for the current operating conditions;
(b)- Quantitatively evaluate the effect of an increase in temperature inside the cold room in the diffusion rate
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