Periodic boundary condition

Can the periodic boundary condition be applied to a transient model (laminar flow equation).

I have a fairly complex geometry which has a repeated pattern. I am hoping that I can use a small subset of it and use the periodic boundary condition in the transient state to find the solution rather than using the complete model which would have way too many DOFs.

Is this possible? How do I implement this?

Note that this model consists of a pipe with a perforation