find percentage of impaction in autodesk CFD
 

Hi,
I am working on an inhaler project, I would like to know the percentage of drug particles that get stuck in the device. I tried to use "traces" in autodesk CFD and set coefficient of restitution to 0.01, but the residence time shows each time all particles come out of the device. Anyone knows is it possible to find this percentage in CFD and how?

Thanks in advance
Emma