How do I simulate the effects of a ceiling diffuser in Flow Simulation?

Here are the types of ceiling diffuer I encounter in my HVAC analysis of data centers:

and

Do I need to actually model the physical characteristics of each of these within the project or can I just use Boundary Conditions?  If boundary conditions, how to I determine what the Flow Parameters should be?

Thank you!

Renee

SolidworksFlow Simulation