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rookie May 14, 2003 12:14

molar concentration marco

In the multispecies model, we can retrieve species mass fraction using C_YI(c, t, i). Does anyone know what is the marco to retrieve specie molar concentration something like C_YI?

Thank you!

Andrew Garrard May 15, 2003 08:23

Re: molar concentration marco

Andrew Garrard May 15, 2003 08:29

Re: molar concentration marco
I don't know if you can get the UDF to pull out the molar concentration or not. I believe that fluent calculates the mass fraction during the iterative process and then converts this to a molar concentration when requested, for example in a contour plot. You can get your UDF to produce a molar concentration by multiplying the mass fraction by the density and dividing by the molecular weight something like

mol_conc = yi[0] * C_R(c, t) / mw[0];

I don't know if that will you will have to play around with it, but that is how I intend to produce the molar concentration.

rookie June 12, 2003 20:51

Re: molar concentration marco
Hello Andrew,

Your idea works! Thank you a lot.


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