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-   -   cellMixture: multi-component mixture (http://www.cfd-online.com/Forums/openfoam/65697-cellmixture-multi-component-mixture.html)

mgc June 23, 2009 12:25

cellMixture: multi-component mixture
 
Hi all!

cellMixture in multiComponentMixture is defined as:

<<
forAll (i)
{
cellMixture += Y[i] / species[i].W() * speciesData[i]
}
>>

Does anyone know why the mass fracction of i-species is divided by the mol-weight of i-species?

Thanks!
Marķa

niklas June 29, 2009 11:18

Quote:

Originally Posted by mgc (Post 220235)
Hi all!

cellMixture in multiComponentMixture is defined as:

<<
forAll (i)
{
cellMixture += Y[i] / species[i].W() * speciesData[i]
}
>>

Does anyone know why the mass fracction of i-species is divided by the mol-weight of i-species?

Thats because the speciesData is given per moles.

If you are missing the mol-weight of the mixture it doesnt make any difference
if you multiply everything with the same factor

so if it were to read like this
cellMixture += Wtot*Y[i] / species[i].W() * speciesData[i]

you would still get the same results, no matter the value on Wtot, hence you can set Wtot=1.

mgc July 15, 2009 05:59

Have a look at the bug forum


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