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PussInBoots October 4, 2011 05:18

Gasflow into vacuum
I'm totally new to CFD and thus to OpenFOAM. I've been playing around with the tutorials for quite a time and wanted to start simulating my own problem now.
For my job at a university group in Hamburg (Germany) I should simulate the flow of an ideal gas through a nozzle into a vacuum chamber.

On my first tries I got lots of errors (mostly to high Courant numbers) while trying to adapt the "compressible/sonicFoam/laminar/forwardStep" to my mesh and testing it.

1) Is sonicFoam able to simulate such a flow?
2) which boundary conditions are the best for simulating an input of some bars of pressure and how to model the vacuum chamber?

Unfortunately didn't I find appropriate answers in existing threats.

eric.m.tridas October 17, 2011 10:35

Hey Max,

I'm working on a similar project where I am simulating air flow into a vacuum chamber through a controlled leak (0.5 mm ID capillary). I used rhoCentralFoam to get a transient solution. I'm not done with the project yet but I have obtained some reasonable results.

You may want to check out the LadenburgJet60psi tutorial in the rhoCentralFoam section. This helped me greatly when I was first starting.

I hope this helps! Keep me updated as it is always good to be in touch with others working on similar projects.



PussInBoots October 19, 2011 08:06

Hey Eric,

thanks for your reply. I'll keep you posted as soon as I make any progress.


sumeet kotak May 3, 2013 16:29

create vacuum inside chamber....!!???
Hello Max and Eric

I am doing my Project at Mumbai University,India. I am simulating vacuum chamber in my simulation.

I am working on Physical vapor deposition. To improve coating quality I have to maintain vacuum of level 0.005 pascal and my geometry is a vertical cylinder of 300 mm dia and 640mm height and horizontal cylinder of 100 mm height and 150mm dia is connected with the vertical cylinder at the height of 150mm from the bottom. the horizontal cylinder on another side is connected with vacuum pump which create vacuum of 0.005 pascal.

I have given boundary condition as pressure outlet.

So can you please help me how should I set my operating pressure and gauge pressure for pressure outlet BC so I can maintain 0.005 pa vacuum inside the chamber.

I am simulating my problem using species transport model with volumetric reaction.

waiting for replay

thanks in advance

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