[KlausR]

I want to simulate the emptying of an open tank by pumping it out through a nozzle by applying multiphaseInterFoam. I have two liquid phases with different densities and an air phase on top. I have applied a fixedValue outlet flow at the nozzle exit and a zeroGradient pressure boundary at the outlet. I read somewhere else that setting a fixedValue at outlet would not work, but I do not think I have a choice. I get unexpected results however (see attachments).

1) Although the heavy phase is below the nozzle, flow of the heavy phase through the nozzle is observed during the whole run. Why can I not see the top phase flow through the nozzle?

2) At the end of the run, when the tank level is below the nozzle the pressure at the nozzle exit catapults to the highest values and I do not understand why?

Thanks for any help, hint, etc.

- Klaus