Fluent-Mixing Problem

Sundar

Hi guys, I am trying to model a mixing problem. I have fresh feed and recycle and they mix in a pipe with bends. The mixture is fed to reactor and some of the species in the mixture is consumed. I know the composition of species in outlet and at feed and recycle and I have rightly fed those values. I am able to observe the change in the individual species concn, but globally I couldn't observe a change in the mass. What I mean is I am monitoring inlet surface and outlet surface of reactor and species do vary as i expect to be, but the total mass which should be less due to comsumption remains the same. All your responses and insights are most welcome. Any insight in modeling such kind of mixing problems is also most welcome. Thanks Sundar