Mixing Water and Air

[Anonymous]

I am working on modeling a space below a cooling tower that has pipes that drain the water coming from the cooling tower and are fed into condensate pumps. Because the water levels are not above the top edges of the pipes there is air also getting sucked into the pumps causing damage to them. The water enters the space from above, flowing through a grate at ground level into a 57'-0"x11'-8"x9'-4" space with 18" diameter pipes located 15" from the floor. I am trying to model this existing condition, then I will add variations to show my client.

I've been looking on the Help site from autodesk and the other postings, but I haven't seen any way to show a mixture of both Water and Air. Is this a possibilty using Scalar Mixing despite the fluid density differences?

[OmkarJ]

I could not exactly understand your problem. How about posting your domain, or even a handsketch to illustrate it? A well illustrated picture is worth thousand words!

That said, AFAIK, the scalar mixing typically addresses the transport through diffusion and I don't think you can solve for inhomogeneous velocity fields of two independent phases taking into account the interfacial interaction. However it will be interesting to see what Autodesk Support say on this...

[Anonymous]

I have attached a section and overall perspective showing the conditions I'm working with. I need to know how to model the standing water and instead of air I can use massless particles so that I can follow their movement. I need help figuring out how to do the water and add the particles.

Any help is welcome.

[Jon.Wilde]

I would say this is beyond the scope of Sim CFD. You would really need to see the surface tension and bubbles, which we cannot model.