How to understand "Y[inertIndex] = scalar(1)  Yt" in YEqn.H
Hi Foamers:
As we can see the following codes in YEqn.H: { label inertIndex = 1; volScalarField Yt(0.0*Y[0]); forAll(Y, i) { if (Y[i].name() != inertSpecie) { volScalarField& Yi = Y[i]; solve ( fvm::ddt(rho, Yi) + mvConvection>fvmDiv(phi, Yi)  fvm::laplacian(turbulence>muEff(), Yi) == kappa*chemistry.RR(i), mesh.solver("Yi") ); Yi.max(0.0); Yt += Yi; } else { inertIndex = i; } } Y[inertIndex] = scalar(1)  Yt; Y[inertIndex].max(0.0); } What does the "Y[inertIndex]"meas?How can I understand it?and what does the "Y[inertIndex]"use? Thanks in advance! 
I guess:
It is mass fraction of the inert species. For example the N2 mass fraction in the following: CH4+2(O2+3.76N2) > CO2+2H2O+7.52N2 
Thanks Moslem,I think you are right!

All times are GMT 4. The time now is 05:53. 