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-   -   Devolatilisation Models (https://www.cfd-online.com/Forums/openfoam-pre-processing/174500-devolatilisation-models.html)

amin_jalalian July 13, 2016 12:25

Devolatilisation Models
 
Hi
You know we have some devolatilisation models as constant rate model, single reaction, two competing reactions, CPD, FLASHCHAIN,FG-DVC.
In Openfoam we have 2 model only, two simplest models, constant rate and single reaction. They are too simple models and are not accurate.
Does anyone have written a better model for O.F. ?
thanks.

amin_jalalian July 13, 2016 12:55

Units of volatileData
 
Does any one know the units of A1 & E in the single KineticRateDevolatilisationCoeffs --> volatileData portion?
for example (CH4 12 0.5) // (name A1 E)

Junjun Guo March 7, 2020 09:24

Hi Amin,

Did you get more devolatilisation Models? and do you know the units of A1 & E in the single KineticRateDevolatilisationCoeffs.

Thanks,

GabGar June 11, 2020 17:37

¿Could you heps us?
 
I guess units of E are kcal/mol as you can see here: https://www.openfoam.com/documentati...8C_source.html


But I don't know the units of A1, ¿could anyone help, please?

GabGar September 24, 2020 11:38

Answer!!!!
 
I found the answer, units are:
Activation Energy E [J/kmol.K]

Pre-Exponential Factor A1 [s⁻1]


You can see that because kinetic constant is defined in /opt/openfoam7/src/lagrangian/intermediate/submodels/ReactingMultiphase/DevolatilisationModel/SingleKineticRateDevolatilisation, as:


// Kinetic rate
const scalar kappa = A1*exp(-E/(RR*T));


Where RR is the Universal Gas Constant, defined in src/OpenFOAM/global /constants/thermodynamic /thermodynamicConstants.C, which units are [J/kmol.K], so, as T are in [K], that means that E units are [J/kmol.K].


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