problem with mass flow calculations
 

I'm using Fluent to simulate a fluidized bed where there is a lateral inlet of solids and two outlets, top and bottom.

My goal is to separate two distinct solid phases, one of them must be dragged to the upper exit and the other fall through the bottom.

I'm using Eulerian model and as b.c. velocity inlet of solids and outlet pressure where the pressure differential between the outputs generates the air flow inside the riser.

My problem is related to the mass flow in both outputs, because selecting the calculator function I checked the values are zero to both and creating planes nearby of these the values found are much higher than the input, even using averages ​or after long simulation periods.

Someone who has faced similar problem could please help me?

Thank in advance,

Eduardo