Periodic Multiphase with Different BC for Phases
 

Does anyone know if it is possible to set an periodic boundary condition for one phase and for the other set an pressure outlet for example?
I am trying to extract the time-averaged flow of water and at the same time extract an residence-time distributions curve from a certain region of the domain. The problem is that by solving exclusively with a periodic bc I would be re-injecting my tracer that should be advected out.

I managed to keep the periodic condition without allowing any tracer to come back by simply setting an automatic command each iteration. I would set the initial portion of my channel as a marked region and maintain its concentration as zero.