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

Increase in reactant concentration

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

Like Tree4Likes
  • 1 Post By eng_s_sadeghi
  • 2 Post By eng_s_sadeghi
  • 1 Post By Jenny_Wong

Reply
 
LinkBack Thread Tools Display Modes
Old   September 17, 2012, 07:09
Default Increase in reactant concentration
  #1
Member
 
Jenny
Join Date: Apr 2011
Posts: 34
Rep Power: 5
Jenny_W is on a distinguished road
Hi Everyone,
I am simulating a reaction in FLUENT. There are 2 reactants and 2 products.
I wrote my own reaction mechanism and it seemed right.
However, when I checked the results, the concentration of one of my reactants increased towards the exit of my computational domain.
This is very confusing because I think that the amount of reactants should reduce as they are converted to the products.
If anyone has faced this problem before or knows what may have gone wrong, please kindly let me know.
Thank you,
Jenny
Jenny_W is offline   Reply With Quote

Old   September 17, 2012, 07:52
Default
  #2
Member
 
eng_s_sadeghi's Avatar
 
Join Date: Mar 2011
Posts: 64
Rep Power: 5
eng_s_sadeghi is on a distinguished road
That may be the reverse flow at outlet. You have not set outlet fuel mass fraction as zero and when it reverses, cames back to domain.
Jenny_Wong likes this.
__________________
Saeed Sadeghi
Ansys Fluent CFD Consultant
eng_s_sadeghi is offline   Reply With Quote

Old   September 18, 2012, 02:36
Default Doubt..
  #3
snh
New Member
 
Snh
Join Date: Aug 2012
Location: India
Posts: 14
Rep Power: 3
snh is on a distinguished road
Quote:
Originally Posted by eng_s_sadeghi View Post
That may be the reverse flow at outlet. You have not set outlet fuel mass fraction as zero and when it reverses, cames back to domain.
Hi,
how to set the outlet fuel mass fraction to zero ?
snh is offline   Reply With Quote

Old   September 18, 2012, 03:17
Default
  #4
Member
 
eng_s_sadeghi's Avatar
 
Join Date: Mar 2011
Posts: 64
Rep Power: 5
eng_s_sadeghi is on a distinguished road
Quote:
Originally Posted by snh View Post
Hi,
how to set the outlet fuel mass fraction to zero ?
Outlet should be as "pressure outlet" to could set the species parameters.
Jenny_Wong and snh like this.
__________________
Saeed Sadeghi
Ansys Fluent CFD Consultant
eng_s_sadeghi is offline   Reply With Quote

Old   September 18, 2012, 10:59
Default
  #5
New Member
 
Jenny
Join Date: Jan 2012
Posts: 11
Rep Power: 4
Jenny_Wong is on a distinguished road
Thank you very much eng_s_sadeghi, I will try it.
Jenny
eng_s_sadeghi likes this.
Jenny_Wong is offline   Reply With Quote

Reply

Tags
chemical reaction, chemkin, reactant, reacting flow, reaction mechanism

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
Reaction with zero reactant.. hard33psingh@gmail.com FLUENT 0 January 21, 2010 04:43
How can I increase Heat Transfer at Domain Interf? B.Simon CFX 3 October 28, 2008 19:53
Concentration Scale Data Interpretation usker CD-adapco 4 October 23, 2007 20:30
negative species concentration again Andrew Garrard FLUENT 0 March 22, 2005 11:36
initial concentration in multicomponent mixtures isidro CD-adapco 0 April 26, 2004 07:40


All times are GMT -4. The time now is 03:17.