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

Species Concentration

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

Reply
 
LinkBack Thread Tools Display Modes
Old   September 18, 2001, 09:07
Default Species Concentration
  #1
Michal
Guest
 
Posts: n/a
Hi,

Is it possible to obtain a concentration of species directly from a solver for a UDF purposes?

Michal
  Reply With Quote

Old   September 18, 2001, 17:16
Default Re: Species Concentration
  #2
KT
Guest
 
Posts: n/a
Yes, you can use C_YI(c,t,i), where c is the cell, t is the thread, and i the species index.
  Reply With Quote

Old   September 19, 2001, 01:48
Default Re: Species Concentration
  #3
Michal
Guest
 
Posts: n/a
Thanks for Your response! One mor question: How to check which species index "i" describe particular species? Michal
  Reply With Quote

Old   September 20, 2001, 14:40
Default Re: Species Concentration
  #4
KT
Guest
 
Posts: n/a
It usually corresponds to the species list in the material panel starting with 0.
  Reply With Quote

Old   September 24, 2001, 02:48
Default Re: Species Concentration
  #5
Greg Perkins
Guest
 
Posts: n/a
Note C_YI returns the species mass fraction not concentration. You will need to convert to get concentration.

Greg
  Reply With Quote

Old   September 25, 2001, 02:32
Default Re: Species Concentration
  #6
Michal
Guest
 
Posts: n/a
Thanks for Your advices!

Another question: How to get a mixture density for UDF directly from a solver? Is it correctly to obtain this value simply by C_R(c,t)?
  Reply With Quote

Old   September 25, 2001, 03:45
Default Re: Species Concentration
  #7
Greg Perkins
Guest
 
Posts: n/a
Yes

so a species concentration is

CONC_i = C_YI(c,t,i)*C_R(c,t)/Mi

where Mi = molecular weight g/mol = kg/kmol of species i

Greg
  Reply With Quote

Old   September 25, 2001, 03:52
Default Re: Species Concentration
  #8
Michal
Guest
 
Posts: n/a
Thanks for Your very helpful answer! Now it is clear...

Michal
  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
Species concentration loss N FLUENT 0 January 12, 2006 12:11
Species concentration at the flow exit Kavitha FLUENT 5 May 28, 2005 07:24
negative species concentration again Andrew Garrard FLUENT 0 March 22, 2005 12:36
mole concentration of species (kmole/m3) neihad@hotmail.com FLUENT 5 August 6, 2003 01:55
Fidap 7.63: species Concentration Lisa Eastep Main CFD Forum 4 June 22, 1999 20:03


All times are GMT -4. The time now is 08:10.