[fxseu]

hello ,everyone. I am working on a 3D full loop simulation on circulating fluidized bed. I used the Eulerian-Eulerian model to research the multi-phase flow. Now , I encounter a severe problem. I found that the second phase will be transferred from one place to another and there is no connection between the two place. I have tried many ways including changing mesh size , calculating using second order way ,changing initial conditions . However, the problem still exists. So i doubt whether it is inherent error of fluent or not. the following is the model.
And the red arrow is the direction of mass transfer. No direct pipe to connect the two place, however, i monitor the mass of second phase, the mass of upper place is keeping decreasing. I don't know why. anyone know how the reason?