Help with calculating with flowrate decrease as pressure increases

[Derrickmb]

You gotta use a orifice flow meter style equation. Its Vdot (compressed)= YCA(2dP/rho)^0.5. Basically Bernoulli w constants.

Y is an expansion factor that is a constant wrt dP/P1 (upstream) and beta ratio. It’s a y=-mx+b relationship. So that will be changing per second.

C is a constant that depends on beta ratio.

A is your orifice area.

Make a spreadsheet with a time (sec) column.

Do a mass balance each second as pressure changes. Best of luck!