Hi all,

I am simulate fine powders flow out of a hopper using FLUENT 6 Eulerian multiphase model. I applied outflow B.C. along the bottom (nozzle), and applied pressure outlet B.C. along top surface.

Now my problem is: even though the computed result shows that the free surface of particles drops, the mass flow rate along the bottom surface is always zero, which means no powders flow out.

Can you give me some advice on this problem? Thank you in advance.

Derek Jing

When you apply outflow bc the flow should be fully developed. May be in your case, you can try with pressure outlet bc.

hiranya

But I do not know the outflow velocity of the powders at the hopper exit. In this case, how can I apply pressure outlet B.C.?

Thank you very much.

In addition to velocity, I also did not know the solid volume fraction at the hopper exit. These two parameters are required for pressure outlet B.C.

So, how can I apply pressure outlet B.C. ?