species conservation problem

H Patel

Hi

I am simulating a mixing tank with impeller in stady state.My flow domain invoves two species toluene and styrene.I dont have any inlet or outlet boundary condition. i have only wall boundary conditions.To specify initial condition( two seperate layer) i used initialise and patch panel to specify two separate layers for species.for example i created a cell register by selacting cells in top 15% volume. and patched value of 1 for tol in that register.i swithched off species equation and i solved flow equation for 1st order and then swithched on species equation and both species and flow equations are solved.

My quation is when i used fluent's Report menu to calculate vol weighted avg. for mass fraction of toluene,It was showing 0.15% before solving but after solving it was showing 0.08%.

Why individual species are not conserved?

Any help will be appreciated.

thanks