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carbonmonoxide pollution in a room

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Old   February 26, 2019, 06:19
Unhappy carbonmonoxide pollution in a room
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Hello everyone,

I would like to simulate the pollution and spread of carbonmonoxide in a room.

The real source is a gas gloud, where constantly 0.04 g/s CO is produced. The cloud has a volume of 0.1178 m.
There is a ventilation system to reduce CO-concentration in the room.
Simulation should be done static.

I implemented the scalar "CO" for carbonmonoxide.

As a source in the simulation I created a blockage of domain material (assumption that CO has almost the same density as air) and set CO source to "fixed flux".

1. Problem is:
I would like to have the concentration of CO as output. (because the limit which is to observe is 0.035g/m)
As I have 0.04kg/s and a cloud of 0.1178m, can I just set a fixed flux of 0.04/0.1178 = 0.3396(kg/s)/m
The does not really exist, but is it okay for this purpose?
(remember: assumptoin that density is the same)

2. Problem is:
I do not really get the difference between "total flux" and "per unit volume".

After reading some explanations in the POLIS I thought that total flux means flux of the whole cloud and per unit volume would be per each little volume of the grid.
But that does not fit the result that I get (concentation results are MUCH higher when using total flux).

Does "per unit volume" mean per m??

which one is right in my case?

Hope someone can help me,

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Old   March 15, 2019, 10:52
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Assuming that the source is 0.04g/s and not 0.04kg/s of carbon monoxide, then you can either set 4.0E-5 as the total flux, or 3.396E-4 as the flux "per unit volume".

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contaminants, fixed value, per unit volume, scalar, total flow rate

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