[Munggang]

Hi,

I've seen interesting discussions on the cyclone separator in this forum. However, I still encounter some problems with my cyclone modelling. Hence, I'd be glad if somone can help me finding what's wrong with my set up parameters.

I'm working with cyclone separator commonly used in geothermal power station to separate steam and water from two phase fluid. The design is quite similar with cyclone separator used to separate gas and solid. The different is in the shape geometry and the directin of the inner pipe which goes into the bottom instead of the top (refer to this drawing http://postimage.org/image/mp5qddn2r/).

I use tetrahedrons for meshing.

I define the inlet as velocity inlet, the steam outlet as pressure outlet and the water outlet as pressure outlet. I use RSM model (mixture, slip velocity, number of eulerian phase: 2, reynolds stress, linear pressure-strain, wall reflection effects, standard wall functions).

For disretization, I use Simple, Green-Gauss Node Based, Presto!, 2nd order upwind, Quick, 2nd order upwind, 2nd order upwind.

The problem is the iteration never converges below 0.01 (I expect it to be as low as 0.0001). Besides, the result never indicates that the steam will move up the vessel, entering the inner vessel. It seems that the two phase fluid just go directly into the water outlet, without any swirling or cyclone movement.

Does anybody have any suggestion on this?

Thanks in advanced.