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Missing division by dt in COxidationMurphyShaddix

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Old   May 17, 2010, 15:43
Default Missing division by dt in COxidationMurphyShaddix
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Hello,

In the Murphy-Shaddix submodel for char oxidation:
src/lagrangian/coalCombustion/submodels/surfaceReactionModel/COxidationMurphyShaddix/COxidationMurphyShaddix.C

In the statement:
const scalar qVol = sum(dMassVolatile)/(WVol_*Ap);

This is supposed to be a molar rate [kmol/m^2/s], so it should be divided by dt.

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Old   May 17, 2010, 15:59
Default Calculating heat-of-reaction in submodel: COxidationMurphyShaddix
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In the char-oxidation submodels under:
OpenFOAM-1.6/src/lagrangian/coalCombustion/submodels/surfaceReactionModel/
for: C(s) + O2(g) => CO2(g)

[COxidationDiffusionLimitedRate] and [COxidationKineticDiffusionLimitedRate] calculate the heat of reaction based on the enthalpies of formation (i.e., chemical specific enthalpy), whereas [COxidationMurphyShaddix] calculates it based on the total (i.e., chemical plus sensible specific enthalpy) specific enthalpies.
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Old   May 18, 2010, 12:22
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Are you running OpenFOAM-1.6.x? It appears that the code snippet you posted is out of date and the latest version is in our git repository.

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Old   May 18, 2010, 15:19
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Thanks for the reply.

I am running 1.6. However, I see that you advise me to switch to 1.6-x which seems to have addressed several implementation mistakes in 1.6.

Thanks.
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