|
[Sponsors] |
April 5, 2010, 21:31 |
Species transport model problem
|
#1 |
New Member
Ján
Join Date: Mar 2010
Location: Slovakia
Posts: 24
Rep Power: 16 |
Hi,
I ve got a problem with species transport model reaction simulation. I have to simulate a supersonic combustion 2H2+O2->2H2O in a nozzle. Because of supersonic flow I use a coupled solver and standard k-eps and thats why I use species transport. Problem is, that when I try to use eddy-dissip. interaction model there was no reaction at all. Initializing of solution with high temperature and non zero fuel content does not help. And when I adjust the high temperature condition at pressure inlet (in some cases I need 1800K and maybe more) the solution has a convergence problem (courant number set to 0.5 and no solution). Some ideas why the reaction mechanism does not work? For instance, how the fluent knows an activation energy of the reaction by using eddy-dissip? Its good idea to use a eddy-dissip? Thank you very much in advance... |
|
August 28, 2010, 22:15 |
|
#2 | |
New Member
aditya
Join Date: Aug 2010
Posts: 10
Rep Power: 16 |
Quote:
|
||
October 19, 2010, 09:08 |
|
#3 |
Member
Marta Lazzarin
Join Date: Jun 2009
Location: Italy
Posts: 71
Rep Power: 17 |
Hi All, I am experiencing the same problem, but i cannot use the coupled solver, because my laptop can't afford occupying all that memory.
Now I am trying using lower relaxation factors for species conservation equations. Up to now, i did not manage to make my simulation converge. Have you found a solution? Thanks in advance, Marta |
|
March 11, 2013, 12:16 |
|
#4 |
Member
Jenny
Join Date: Apr 2011
Posts: 34
Rep Power: 15 |
Hi Everyone,
I am modelling compressible non-combustion reacting flow in FLUENT and facing the same problem. I tried all species transport models and increasing inlet temperature but they didn't work. If anyone knows what may have gone wrong, please give me some suggestions. Thank you, Jenny |
|
March 11, 2013, 13:17 |
|
#5 | |
Member
Ernesto
Join Date: Dec 2011
Posts: 30
Rep Power: 14 |
Quote:
Hello Jenny, can you be more specific on what is happening? Are reactions not happening at all? |
||
March 11, 2013, 17:50 |
|
#6 |
Member
Jenny
Join Date: Apr 2011
Posts: 34
Rep Power: 15 |
Hi,
Thank you for your reply. I am modelling atmospheric reactions which are not available in FLUENT library. I have to fill in the reaction mechanism (including kinetic parameters) in the reaction panel. I use k-e model. I choose species transport and turbulence-chemistry interactions (laminar finite rate, EDC etc). After setting BCs, I initialise and patch a region of high temperature. The simulation runs for a few thousand iterations but there was no reaction - no products formed and the kinetic rate of reaction is zero. Would you advise what could have gone wrong? Thank you, Jenny |
|
March 11, 2013, 19:02 |
|
#7 | |
Member
Ernesto
Join Date: Dec 2011
Posts: 30
Rep Power: 14 |
Quote:
You also have to patch in the products of the chemical reaction in order for it to procede. Hope this helps |
||
March 12, 2013, 04:50 |
|
#8 |
Member
Jenny
Join Date: Apr 2011
Posts: 34
Rep Power: 15 |
Hi Ernesto,
I will do that. Thank you very much for your help. Regards, Jenny |
|
September 20, 2019, 08:23 |
Scramjet combustion
|
#9 |
New Member
Jeyakumar
Join Date: Aug 2018
Location: India
Posts: 1
Rep Power: 0 |
Can any one suggest for scramjet combustion procedure using ansys fluent?
|
|
Tags |
species transport |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
questions about species transport through walls | shuqin | FLUENT | 13 | April 9, 2014 03:42 |
Species transport | Eisa | FLUENT | 0 | May 17, 2006 09:26 |
Species transport | Eisa | FLUENT | 0 | May 17, 2006 05:40 |
problem with MFR model for multiphase mixing tanks | Srinivas | Main CFD Forum | 1 | November 7, 2005 15:16 |
3D species transport model - 1 | co2 | FLUENT | 1 | April 23, 2004 05:20 |