Particle tracking results are nonsense

Paul

Okay I'm working on a project in order to prove to a client the feasibility of us using CFD to accurately predict how our designs are going to operate. I'm running a model right now in which there is a plate with static vanes. It looks like a fan if you're looking down on it but the vanes themselves don't actually move. The air passes through them and circulates.

Working on several different equation sets I've found that the RSM unsteady model provides for the most accurate velocity and pressure drop results. 2nd order is even better but I can't get it to converge (thats another problem to deal with later).

Unfortionately I can't get the particle tracking to make any sense whatsoever. When I use the rosin-rammler distribution for the injection I get maybe 30% efficiency (70% of the particles escape the apparatus through the outlet at the top) which is completely wrong for this design. Maybe there would be some variation, but 30% efficiency is way off.

If I use a uniform particle distribution, it goes from about 0% efficiency to 100% efficiency changing the particle diameter size from 70 to 90 microns, which is also wrong because there should not be that great of a chance with such a small change in particle diameter.

I did not have the descrete phase enabled during iterations, because if I do the simulation undoubtably crashes or the results get so skewed and make no sense whatsoever.

Does anybody have any advice of what I can do? A major part of this project is being able to give accurate particle efficiencies but I've been banging my head against the walls for days trying to get this to work.

Thank you.