u/OkAnybody2762

Dear all,
I have recently (for about 6-months) started using openFOAM since I ran into limitations in Autodesk’s CFD.
For now, I have used pre made tutorial examples and tweaked them by using parts from the multiple OpenFOAM user manuals - I have V13.

But I still can not accurately determine the pressure and velocities of my gas flow inside a cylinder with a pressure drop from the mbar range to 1E-3 mbar range.

Does anyone have an idea of where I could start for this? Is there specific packages that are useful for this, which I don’t know of? I have so far used the basics. My geometry is a simple cylinder with an entrance of diatomic gas applied with few mBar’s and ending in the vacuum regime.

Thank you in advance:D