Problems with particles & boundary conditions

Simon Steinmeyer

Hello,

I have a furnace with a grate where I have to put wood particles on it. It is a special grate which transports the particle with 3cm/sec.

Now my problem: I have chosen a porous jump with the boundary condition "reflection". Then I injected the particles with a speed of 3 cm/sec just over the porous jump. Gravity has been enabled.

The result it that my particle are jumping all the time because fluent does not know friction. Then the turbulent air flow causes to spread them in a chaotical manner.

The other possibilities "trap" and "escape" are not suitable, too. Walls support to modify the reflection with a polynom but I cannot use them because they are not porous for air flow.

How can I force my particles to stay on the grate?

Thanks, Simon Steinmeyer