[Loekatoni]

Dear foamers,

I have questions regarding and inlet profile which is partially negative and partially positive.


My model needs to become a horizontal channel (picture of schematics is added below). To limit the amount of gridcells, I am modelling a inifinitely small angle of the channel in the theta direction, practically making it a 2D problem. So now I have the top which is the wall of the channel, the bottom which is the centre of the channel and the left and right are respectively the in- and outlet of the channel and front and back are defined as empty.


Eventually I'm going to model flow, masstransfer and kinetics around a bubble. So the profile is kind of funky. The bubble is the reference frame. So I calculate the flowprofile of a liquid through a channel without the bubble via Hagen-Poiseuille and substract the bubble velocity to obtain the flowprofile for a system with a bubble as the frame of reference. When I do this, part of the final flow balance is negative and part is positive. If I try to use the codedFixedValue boundary, I get unphysical results. I haven't heard of another way to induce a profile on a boundary.


So my questions here are:
Does anybody has any experience with this kind of flow profile input?
Is there any other boundary to use to impose a profile on a boundary in which I write an equation?


Sincerely,
Loek