|March 29, 2012, 10:17||
Ventilation to reduce the CO2 concentration
Join Date: Oct 2010
Posts: 302Rep Power: 9
I'm simulating the air flow inside a room to investigate the effectiveness of ventilation in reducing the CO2 concentration in the room.
The domain is a simple room with ventilation inlets and ventilation outlets.
The human breathing ( Inhalation of O2 and Exhalation of CO2 ) has to be modled in the room.
I considered 3 such human sources of CO2 in the room.
From a biomechanics journal I found the graphical data for the breathing cycle in humans.
The journal reports the cycle for a time of 4 [s] .
However I feel that if my purpose is just to see the effectiveness of ventilation in the room then a time of 4 [s] is too short.
so I'd like to see a more realistic situation by allowing the ventilation to occur for about 10 minutes.
Also I feel that it would be apt in this case to select the maximum flow rate for breathing from the graph ( breathing cycle )
And use it to model the human sources instead of simulating the entire cycle itself.
Since the purpose is only to investigate the effectiveness of ventilation in terms of reducing the CO2 concentration in the room.
Could some one please comment on this approach.
|March 29, 2012, 23:46||
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 11,057Rep Power: 86
Your thinking is correct. If your model is a slow time scale then you (hopefully!) can compress the complex short time scales into a time-averaged effect for a long time scale simulation.
I will leave it up to you to determine if the velocity of a person's breath is signfiicant, in your case I doubt it but I do not know the details of what you are doing. In that case then a fairly simple approach which uses a sink on the O2 concentration and a source on CO2 should feasible, with the rate matched to the time-averaged rate.
|Thread||Thread Starter||Forum||Replies||Last Post|
|CO2 concentration simulation||angierain||CFX||5||June 16, 2011 18:57|
|Problems with defining high initial concentrations of CO2||Lizzz||FLUENT||0||August 11, 2010 05:34|
|Concentration of CO2 Modelling help||kingjewel1||CFX||7||July 23, 2009 06:20|
|initial concentration in multicomponent mixtures||isidro||CD-adapco||0||April 26, 2004 07:40|
|CFD simulation on CO2 distribution||Apple L S Chan||Main CFD Forum||3||July 18, 1999 10:05|