CFD Online Logo CFD Online URL
Home > Forums > General Forums > Main CFD Forum

3-D Contaminant Dispersal Simulation

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Search this Thread Display Modes
Old   December 21, 1998, 23:46
Default 3-D Contaminant Dispersal Simulation
Apple L S Chan
Posts: n/a
Dear all

First of all, Merry X'mas!

I am a PhD student and now conducting CFD simulation on CO2 contaminant distribution. First of all, a converged solution of velocity and temperature distribution has been obtained by a CFD program. Then the transport equation for CO2 concentration is going to be solved based on the simulated velocity and temperature field. I have three questions and would like to have valuable advices from someone.

(1) In the simulation of CO2 concentration distribution, 700ppm of CO2 is input in air supply inlet. Is it also necessary to input any ppm value of CO2 in the exhaust outlet in order to have conservation of mass (CO2)? If yes, how can I know the ppm value of CO2 near exhaust outlet before the CO2 concentration distribution simulation?

(2) Since the CFD code I am using is a non-commercial one, it seems that there is no input of the CO2 density. Then how can I tell the simulation program that the gas is CO2 or other gases? I would like to know the input method in other similar CFD program.

(3) In my CO2 concentration distribution simulation program, only maximum time iteration step is input to control when the simulation will be terminated. I would like to know in other similar program, is there any input as convergence or divergence criteria for such simulation?

Thank you very much!

Apple Chan (from Hong Kong) 22 Dec. 98
  Reply With Quote

Old   December 23, 1998, 11:06
Default Re: 3-D Contaminant Dispersal Simulation
I. Dotsikas
Posts: n/a
1.) Your code should be able to maintain the amount of CO_2 you introduced in the inlet. The concentration may vary, depending on your Outlet. By using a conservative Diskretisation and assuming that no chemical Reaction is taking place, you shouldn't get more or less CO_2. (CO_2 doesn't vanish ) Use zero gradient at outlet.

2.) You may use the density of your mixture. Notice that the density of mixtures may be difficult to calculate. ( Take a look at The Properties of gases and liquids: Reid,Prowsnitz ). By a Concentration of 700 ppm you may use the density of your Medium ( Air or what else you have ) If you want a more precise answer I have to know more about your Problem. You need actually should need only the mass flow rates through the boundaries of your kontroll volumes which are provided from the CFD Routines.(Finite volumes Diskretisation)

Merry Christmas and good luck
  Reply With Quote


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Solar Radiation in OpenFOAM plainstyle OpenFOAM Running, Solving & CFD 15 July 8, 2014 05:43
Simulation of a complex wing in solidworks flow simulation niels1900 FloEFD, FloWorks & FloTHERM 6 April 20, 2011 11:44
GUI crash and simulation engine still running RPJones FLOW-3D 2 November 9, 2010 09:18
velocity profile export from a simulation onto another sudhirlv STAR-CCM+ 1 September 12, 2010 19:57
strange simulation error Ralf Schmidt FLUENT 2 May 4, 2007 14:02

All times are GMT -4. The time now is 20:58.