Thanks very much for all your replies,
ShaunE,
I'm not totally familiar with the problem, and am asking the question on behalf of someone else; but I know that the pressure drop doesn't need to be controlled, as the different flow rates occur in discrete situations.
Cheers for your advice...
I wish to simulate the pressure drop of air going through a filter by the use of a multi-orifice plate. There are a number of flow rates that can exist but the pressure drop must stay the same for each of the flow rates. I need to know what total area of holes in the plate, is required for the...