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Zhiheng Wang August 28, 2016 07:08

>Regarding chemistry
 
Hi
How can I write reaction of CO2 decomposition in openFoam it is reversible reaction

[CO] + 0.5 [O2]^0.25 --> CO2 ( Aforward = 2.24*10^12 [kMOL/M^3]^(-0.25)/second , Ea= 1.1674*10^8 J/kMOL

[CO2] ------> [CO] + 0.5 [O2]^0.25 ( Areverse = 5.0*10^08 [kMOL/M^3] , Ea= 1.1674*10^8 J/kMOL)

where Ea is activation energy and A is per-exponant

I dont know how to write A for reversable Arrhenius reaction in openFoam

a_slow_old_man October 28, 2016 05:01

Hello Zhiheng,

you can try to use two Irreversible Arrhenius reaction.

One for the Forward reaction with the given values, and another one for the reverse.

Zhiheng Wang December 30, 2016 05:54

two reactions
 
But How does one irreversable and one reversable reaction get solved by ods , where to look for it

a_slow_old_man January 8, 2017 05:34

1 Attachment(s)
Hello Zhiheng Wang,

If I understand you correct you want to model ONE reversible reaction:

CO + 0.5 O2 <=> CO2

You have the parameters A and Ea for both the forward and reverse reaction.

I had the same problem with a methane combustion reversible reaction but used a double irreversible reaction. One for the forward and one for the backward reaction. Just two irreversible ones and together they make one reversible one.

In your example it should look like the file I attached. Use chemkinToFoam on it and if your A and Ea are correct it should work if I did not mess up in there.


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