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Old   August 28, 2016, 07:08
Default >Regarding chemistry
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Zhiheng Wang
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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
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Old   October 28, 2016, 05:01
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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.
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Old   December 30, 2016, 06:54
Default two reactions
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Zhiheng Wang
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But How does one irreversable and one reversable reaction get solved by ods , where to look for it
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Old   January 8, 2017, 06:34
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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.
Attached Files
File Type: zip CO2-2Step.zip (6.7 KB, 11 views)
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