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

Mixing in porous media

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

Reply
 
LinkBack Thread Tools Display Modes
Old   April 17, 2009, 12:34
Default Mixing in porous media
  #1
Senior Member
 
Aroon
Join Date: Apr 2009
Location: Racine WI
Posts: 148
Rep Power: 8
vishyaroon is on a distinguished road
How good (are trustable) are predictions of mixing of two fluids in porous regions (any software - Fluent, STAR)? I know from the basic formulation of porous media, that the constants are defined for computing the pressure drop across the region, but can we believe the results of mixing of two fluid streams in the region?
vishyaroon is offline   Reply With Quote

Old   April 17, 2009, 21:19
Default
  #2
otd
Member
 
private
Join Date: Mar 2009
Posts: 74
Rep Power: 8
otd is on a distinguished road
Are mixing liquids, gases, both?
otd is offline   Reply With Quote

Old   April 18, 2009, 01:29
Default
  #3
Senior Member
 
N/A
Join Date: Mar 2009
Posts: 188
Rep Power: 8
harishg is on a distinguished road
Trial and error and literature survey is what you need to do.
harishg is offline   Reply With Quote

Old   April 18, 2009, 16:13
Default
  #4
Senior Member
 
Aroon
Join Date: Apr 2009
Location: Racine WI
Posts: 148
Rep Power: 8
vishyaroon is on a distinguished road
I am looking at two gases that mix as they pass through a porous zone.
vishyaroon is offline   Reply With Quote

Old   April 19, 2009, 14:11
Default
  #5
otd
Member
 
private
Join Date: Mar 2009
Posts: 74
Rep Power: 8
otd is on a distinguished road
Sorry I didn't read your question closely. It appears you are asking about the ability of Fluent to do your problem.

Have you asked the question on the Fluent forum or, perhaps, asked the Fluent support staff directly?
otd is offline   Reply With Quote

Old   April 19, 2009, 17:49
Default
  #6
New Member
 
Join Date: Mar 2009
Posts: 5
Rep Power: 8
andy2o is on a distinguished road
Consider these two examples of domains which could be modelled as porous medium flows, but have very different mixing characteristics:

1) Flow through many parallel micro-channels - which will permit zero cross-flow mixing because the flow is confined to the individual channels.
2) Flow through a random bed of spheres, where fluid will be spread as it hits each sphere, causing cross-flow motion which will help mixing.

I guess your application lies somewhere between these extremes. The point is that a drag correlation only computes the drag. It does not distinguish between these two different mixing scenarios. Therefore you need to supply a model for the effective momentum and mass diffusion caused by the porous medium as well as the drag force to complete your model of a porous medium. This diffusion model will need to take the form of correlation / approximation based on experimental data (or perhaps very detailed CFD) just like the drag coefficients do.

As always: The results will be only as good as the correlation! So you can only trust the results if you trust your correlation and validate your model!!

Best regards,
andy2o
andy2o is offline   Reply With Quote

Old   April 20, 2009, 08:41
Default
  #7
Senior Member
 
Aroon
Join Date: Apr 2009
Location: Racine WI
Posts: 148
Rep Power: 8
vishyaroon is on a distinguished road
Thank you all for replying to the question. I guess as Andy mentions I'll have to do a detailed CFD or get some correlataions based on experiments.
vishyaroon is offline   Reply With Quote

Reply

Tags
mixing, porous media

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
Porous Media coupled with internal flow Samuel Andrade FLUENT 2 August 26, 2012 09:43
Mixing in porous media vishyaroon STAR-CCM+ 0 April 17, 2009 10:43
species mass source in porous media ? PK FLUENT 0 February 16, 2007 12:12
Two phase flow in porous media Madhavi Krishnan FLUENT 3 June 6, 2005 05:52
porous media: Fluent or Star-CD? Igor Main CFD Forum 0 December 5, 2002 16:16


All times are GMT -4. The time now is 23:26.