TASKS 1. The test room has the following dimensions: A x B x C. The air change rate is k1

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TASKS

1. The test room has the following dimensions: A x B x C. The air change rate is k1. At 9:15 a.m. n people enter the room. After 1.5 h the room was leaved and air change rate increased 2 times.

How long will it take before the air in the room returns to the equilibrium with ambient air?

The data is provided in Table 1.

No Cambient [ppm] A x B x C k1 [h^-1] n

1 360 5x6x2.5 0.5 9

2 340 6x6x2.5 0.7 12

3 320 7x6x2.5 0.8 14

4 380 8x6x2.5 0.9 16

5 360 9x6x2.5 1 18

6 340 10x6x2.5 1.2 20

7 320 5x10x2.5 1.4 9

8 380 5x9x2.5 1.6 12

9 360 5x8x2.5 1.8 14

10 340 5x7x2.5 2 16

11 320 5x6x2.5 2.2 18

12 380 5x5x2.5 2.4 20

2. Calculate and display the temporal variation of CO2 concentration in the room in course of 4 h since the time when people entered the room.

3. Calculate concentration of the emitted substance as a function of the vertical distance from the ground, at the downwind distance of 2 km from the emission source. The emission and dispersion conditions are as follows:

Substance emitted: SO2; Emission rate: 30 g/s;

Emitter height: 75 m;

Vertical distance range: 0:200 m;

No Atmospheric stability

Wind speed

Terrain

1 1 1 Fields

2 2 1 Forest

3 3 1 Village, congested housing

4 4 1 Fields

5 5 1 Forest

7 1 3 Fields

8 2 3 Forest

10 4 3 Fields

11 5 3 Forest

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