CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > CFX

Mixing of air and CO2

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

Reply
 
LinkBack Thread Tools Display Modes
Old   August 24, 2011, 16:36
Default Mixing of air and CO2
  #1
New Member
 
Tobias
Join Date: Aug 2011
Posts: 5
Rep Power: 5
unischlaf is on a distinguished road
Hi, I have no experience with CFX Pre. So I hope someone can help me. I would like to calculate the mixing of CO2 after a nozzle with air. In the sketch you can see the construction.

I have 2 meshes. One for die nozzle and one for the pipe. Therefore there is a interface at the end of the nozzle (red marked).

Now my question: What I have to set in CFX Pre for both domains? In the domain of the lance I have set "CO2 ideal gas" (calorically perfect ideal gas) as material. I think that's right. But what should I set in the other domain? Is it enough to set "ideal gas" as material. Or do I consider CO2 as material?

Can someone tell me the correct settings, please? Thank you!
Attached Images
File Type: jpg Unbenannt.jpg (34.7 KB, 17 views)
unischlaf is offline   Reply With Quote

Old   August 24, 2011, 18:46
Default
  #2
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 9,378
Rep Power: 74
ghorrocks has a spectacular aura aboutghorrocks has a spectacular aura aboutghorrocks has a spectacular aura about
No need for multiple domains. Just use a single domain. Use a multicomponent gas if you want to fully model the mixing process, but you could simplify this model down to a single component (ie air) and add the CO2 as an additional variable if you like. This is much simpler, but does not take into account the full fluid property changes due to mixture composition. Whether these fluid property changes are significant enough to mean a multicomponent mixture model is required is up to you.
ghorrocks is offline   Reply With Quote

Old   August 25, 2011, 03:09
Default
  #3
New Member
 
Tobias
Join Date: Aug 2011
Posts: 5
Rep Power: 5
unischlaf is on a distinguished road
Now I have the following settings:

1 domain for both meshes
in Fluid and Particle Definitions: Ideal Air Gas und CO2 Ideal Gas as Continuous Fluid
Turbulence model for both fluids is SST

At the nozzle inlet I have set the Bulk Mass Flow Rate and Volume Fraction of CO2 is 1 and of Ideal Air is 0.
At the pipe inlet I have set the Bulk Mass Flow Rate and Volume Fraction of CO2 is 0 and of Ideal Air is 1.

Is that ok?
unischlaf is offline   Reply With Quote

Old   August 25, 2011, 18:45
Default
  #4
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 9,378
Rep Power: 74
ghorrocks has a spectacular aura aboutghorrocks has a spectacular aura aboutghorrocks has a spectacular aura about
Sounds sensible.
ghorrocks is offline   Reply With Quote

Reply

Thread Tools
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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
CO2 concentration simulation angierain CFX 5 June 16, 2011 18:57
How to change simulated fluid from air to C02 Aerospace OpenFOAM 6 May 27, 2011 12:26
mixing Eddy FLUENT 0 November 16, 2005 12:30
Mixing in co-axial jets sudeep CD-adapco 0 February 13, 2001 08:42
CFD simulation on CO2 distribution Apple L S Chan Main CFD Forum 3 July 18, 1999 10:05


All times are GMT -4. The time now is 05:10.