[Mic_N]

Greetings all, occasional lurker and CFD newbie here looking for some help from those that really know this stuff.

As the title suggests, I'm trying to find some way to simulate and experiment with air lift and geyser pumps... for those who don't know what they are, and air lift pump is the sort of thing used by dredgers and in sewage works, where a vertical submerged pipe has air pumped in at its base.. as the air bubbles rise in the column it draws the water with it, creating what can eventually become a significantly powerful vacuum effect at the base. Geyser pumps work in a similar nature, but with 'holding' chambers into which a volume of air can slowly be built and released once it's displaced enough water and built a 'plug'..

example video at http://www.youtube.com/watch?v=OQqz8yR7sF8



So basically, I'm trying to find something reasonably simple that can roughly simulate both air and water. Doesn't have to be super-accurate, doesn't have to be particularly pretty, and 2D is perfectly acceptable.. Just looking at something that can get that mix of different compressible and incompressible fluids (hopefully with some sense of buoyancy and surface tension) that I can drop some solid structures around to see how different setups compare.


Am I asking for the impossible?

Would really appreciate anything you guys could suggest.

[Mic_N]

So... no-one?

Just a simple, 2D simulation of a volume of air building in a space bounded by (and therefore acting against) a body of water? No recommendable packages or places to start?

[tas38]

Originally Posted by Mic_N

Greetings all, occasional lurker and CFD newbie here looking for some help from those that really know this stuff.

As the title suggests, I'm trying to find some way to simulate and experiment with air lift and geyser pumps... for those who don't know what they are, and air lift pump is the sort of thing used by dredgers and in sewage works, where a vertical submerged pipe has air pumped in at its base.. as the air bubbles rise in the column it draws the water with it, creating what can eventually become a significantly powerful vacuum effect at the base. Geyser pumps work in a similar nature, but with 'holding' chambers into which a volume of air can slowly be built and released once it's displaced enough water and built a 'plug'..

example video at http://www.youtube.com/watch?v=OQqz8yR7sF8



So basically, I'm trying to find something reasonably simple that can roughly simulate both air and water. Doesn't have to be super-accurate, doesn't have to be particularly pretty, and 2D is perfectly acceptable.. Just looking at something that can get that mix of different compressible and incompressible fluids (hopefully with some sense of buoyancy and surface tension) that I can drop some solid structures around to see how different setups compare.


Am I asking for the impossible?

Would really appreciate anything you guys could suggest.

There are many multiphase flow solvers available of varying complexity. For example,
you can take a look at the pre-compiled OpenFOAM solvers such as interFoam and interPhaseChangeFoam. Commercial packages such as Ansys Fluent and CFX also have multiphase flow capability.

If your goal is to qualitatively compare various designs, it is likely that a simpler model, such as an isothermal VOF-based method should suffice. However, VOF methods often do not include surface tension effects. You will have to look into the
particular model details and decide if the most significant physics associated with
your problem are captured.

[Mic_N]

Thanks for the info, very much appreciated and gives me a good idea on where to start.