Hello all,

I am simulate fine powders flowing through the nozzle of a hopper, and the top of the hopper is open to the environmental air.

I am using FLUENT 6.0 Eulerian multiphase model. I apply outflow B.C. at both the bottom (nozzle) and the top of the hopper.

Now there are unreasonable results in the region near the hopper top. I am afraid the B.C. I applied along the top face is not correct.

So, what kind of B.C. shohld I apply for the top face of hopper, outflow, pressure-inlet or pressure-outlet? Thank you very much.

-Derek Jing

Hi1 Why don't you use pressure-outlet as BC where the hopper is open to the environmental air? Yvonne