PeriodicChannel Tutorial -- unphysical solution?

Submitted by Lowered on Fri, 08/18/2017 - 17:09

Hello,

while running periodicChannel tutorial I found some results I'm not able to explain:
the velocity of the fluid has a value of up to 10.19 m/s where the largest part is the x component.
The initial conditions in the CFD part are 0 or zeroGradient for all boundaries. Gravity is acting in z-direction. Inlet and outlet are defined as cyclic.
In DEM there is a particle velocity of 1 m/s in z-direction.

Doe's anybody has an explanation for this behavior?

Later I want to modify this case to some kind of cavity with some filtration at the bottom.

Thank's a lot,
Henrik

alice's picture

alice | Mon, 08/21/2017 - 14:50

Hello Henrik,
the flow velocity (desired mean velocity) is set in the fvOptions file which lies inside the system folder. You'll see that a value of (10 0 0) is set there, leading to the observed velocity in x direction. The particle velocity of (0 0 1) is only chosen for speeding up the insertion of the particles.
Cheers,
Alice