[bgoeppner]

Hello everybody,

my name's Ben and I'm currently writing my diploma/master-thesis in physics. Therefore I need to do some cfd-simulations (in fact most of the thesis is about simulation...) and was wondering if OpenFOAM would be suitable for my purpose. Unfortunatly my own research didn't lead to any satisfying results concerning this question so now I'm hoping you guys could help me out there...

The main question I could not find an answer to is: For what dimensions is OpenFOAM good for? When will there occur larger errors due to numerical limitations? In my special case I have to simulate the flow of a compressible gas (or even better: plasma) through a nozzle with a diameter of only approx. 150-200 mu (0.15 to 0.2 mm) at the narrowest spot. The velocity will be in supersonic range (in fact, that's what the nozzle is good for... ), so shockwaves will apear. Most likely there will be turbulences. The pressures I am dealing with are in between 10^5mbar at the inlet to 0mbar (vacuum) at the outlet. Both inlet and outlet pressure will be constant values.

My predecessor used to go with FLUENT, but as this is a commercial software I was hoping OpenFOAM could become my first choice... Furthermore, FLUENT was having some problems with vacuum, so we had to set pressure at the outlet to about 40mbar... Ok for first impressions but not good for further improvement...

So: Do you think I should spend some more time on creating my own solvers or is it unrealistic at all to simulate those conditions with OpenFOAM?

Lookin' forward to your answers...

Thanks in anticipation.

[herbert]

Hi Ben,

of course OpenFOAM can also deal with your problem as well as Fluent can do. I don't see any problems except for you will have to invest lots of time for getting used to OpenFOAM (normally more than with Fluent).

Good luck
Stefan