CFD Online Logo CFD Online URL
Home > Forums > OpenFOAM

Setting up reaction parameters for a 3-step oxidation mechanism of C3H8

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

LinkBack Thread Tools Display Modes
Old   January 18, 2011, 15:06
Default Setting up reaction parameters for a 3-step oxidation mechanism of C3H8
JosÚ Rodrigues
Join Date: Jun 2010
Location: IN+/IST Lisbon
Posts: 53
Rep Power: 9
jose_rodrig is on a distinguished road

I intend to simulate the oxidation of propane in a combustion chamber with a 3-step mechanism:

C3H8 + 1.5 O2 = 3 CO + 4 H2

CO + 0.5 O2 = CO2

H2 + 0.5 O2 = H2O

For that I ll use reactingFoam solver and the built-in chemistryReader of OpenFOAM.

So, in order to setup the reaction kinetics and mechanism in the reactions dict, I look up in the literature and found out the mechanisms and parameters proposed by Westbrook and Dryer (1981b)

Unfortunately, this mechanism takes into account 2 extra parameters other than activation energy, beta and the frequency factor. In fact, he proposes the following equation:

R = A exp( -Ea/(RT) ) [A]^a [B]^b , with beta=0

A. Is there any reaction type library that might account for this extra parameters? (in contrast with irreversibleArrheniusReaction that accounts only A, beta and Ea).

B. If the answer to A. is negative, can somebody point the file in the source that calculates the reaction rate, so one can try to modify it?

Thank you in advance!
jose_rodrig is offline   Reply With Quote

Old   January 19, 2011, 03:56
Senior Member
Karl-Johan Nogenmyr
Join Date: Mar 2009
Location: Link÷ping
Posts: 275
Rep Power: 14
kalle is on a distinguished road

I know that the chemkin reader also available in OpenFOAM handles this. Have a look in the aachenbomb tutorial, specifically the chemkin/chem.inp-file, where parameters a and b are represented with the FORD keyword. I used westbrook and dryers mechanism with the chemkin lexer in OF without problems.

Good luck!
kalle is offline   Reply With Quote

Old   January 28, 2011, 02:49
Default Reaction File
Senior Member
sahm's Avatar
Seyyed Ali H.M.
Join Date: Nov 2009
Location: Utah
Posts: 103
Rep Power: 9
sahm is on a distinguished road
Hi, Could You please send me your 3 step Propane reaction file?
you can send it to my email or upload it here.
sahm is offline   Reply With Quote

Old   February 4, 2014, 14:25
Default similar problem
New Member
mo houssami
Join Date: May 2011
Posts: 14
Rep Power: 8
mo.houssami is on a distinguished road

I am trying to do something similar but with a 2 step mechanism.
reactions file is fine, but I can't figure out what to put in constant/thermophysicalProperties.

For a single step, I was using the following:

thermoType hsPsiMixtureThermo<singleStepReactingMixture<gasTh ermoPhysics>>;
inertSpecie N2;
fuel CO;

How should I adapt it to add a second reaction with CH4 as the second fuel?

Thank you
mo.houssami is offline   Reply With Quote


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 help!! Harry CFX 4 October 30, 2008 11:11
Multi step reations (80 reactions mechanism) simul Patrick Main CFD Forum 0 August 16, 2008 12:17
setting time step size! raja FLUENT 2 August 14, 2007 08:31
A Problem with setting the time step in VOF model Le FLUENT 2 July 20, 2006 22:00
two step reaction modelling Ahmet Lotfoulahy FLUENT 3 December 21, 2003 10:00

All times are GMT -4. The time now is 05:30.