Buoyancy mixing

[andrea28]

Hi,
I am doing a simulation of two fluid mixing, taking in account the buoyancy effect. I have two inlets and one outlet. The calculation is steady state, and I can't get reasonable solution. I am using the standard k-eps which worked very well with the same case with constant density. I thought the problem was the outlet condition but I tried also the free outlet condition post on this forum, but I get the same results. I attached the listing file, the weird things to me are: the not constant inlet mass flow, and the too high positive y-velocity (due to the geometry the flow should falls down).
Hope you can help me

Andrea

[Luciano Garelli]

Hello,

Did you solve your problem? The convergence in the listing looks good and the change in the mass flow rate may be it is because the fluid changes its density in the case that you has set a velocity inlet or volumetric inlet.

Which is the reasonable solution that are you expecting? Could you give more information about the problem, some sketch or screenshot of the solution?

Regards,

Luciano.

[andrea28]

Thanks for the explanation about the velocity, putting a constant mass flow fixed that. For the results the problem is with the boundary condition on one of the inlet, now I am trying to solve the same problem with the unsteady state, and see if anything changes.
Thanks again

Andrea