Fixed Orifice Plate - choked flow

[Bill3752]

I am evaluating a relief valve case where the governing case includes flow through a fixed orifice plate. Using the Crane equation for compressible gas I am needing to compute the expansion factor Y. The system will take quite a pressure drop across the plate. My question is "For high pressure ratios is there a terminal ratio and Y factor for orifices". When performing a similar calc for nozzles, there is a lower limit for the expansion factor and dP/P is set at choked conditions. Thanks for your input.

 

[Latexman]

For high pressure ratios is there a terminal ratio and Y factor for orifices?

Not for a thin plate orifice. Here's a good post that speaks to that somewhat indirectly: thread798-189979.

Good luck,
Latexman

 

[Latexman]

Took some time to find this one, but it's on topic too - thread798-51260.

Good luck,
Latexman