[ThomasV]

Hello!

Does anyone have a definitive guide for which boundary conditions to choose when simulating e.g. a flow in a pipe with interFoam? I'd be interested to see the BCs for the inlet and outlet patches for alpha, p_rgh and U for both a pressure driven flow (where U BCs use the respective pressures) and a velocity driven flow (where you define certain velocities on both ends)...

My background is that I'm simulating a change of viscosity of the "water" phase depending on temperature and pretty much want to see a higher velocity in the part of the pipe with lower velocity and effectively a slowdown in velocities in areas with higher viscosity. Finding correct BCs is troubling me though. I usually get things working but certain aspects still seem to deliver wrong or strange results. In my case it's all about having a domain that's completely filled by air (alpha = 0) which then gets filled from one side with my liquid (alpha = 1)...

While there exist some discussions about this topic (some of which are outdated now) I never really saw tangible solutions. So if you have working BCs for interFoam it'd be nice if you could share them...