I wish to perform a "rough" simulation of an internal combustion engine's intake port. I intend to have a transient velocity for the opening into the cylinder, which would be the exit for the grid. I will be using StarCD and was wondering if there are any problems I may get to look forward to that anyone has previously dealt with.

Curious why you are not running a "full" simulation. How do you plan to assign physically accurate exit boundary conditions so that you can make realistic conclusions regarding the flow physics in the intake port?

If cost is the issue, then consider (as counter argument) how many iterations of different BC's (none of which may be realistic) you may have to try to make sound conslusions.

Adrin Gharakhani