Accelerating flow for inclined interfoam
 

Hello!

I have an extremely simple simulation in interfoam where water fills a cubic domain up to a certain height. This body of water is supposed to flow under gravity through cyclic boundaries and I expect it to reach a steady velocity at some point. Now, i have applied the changes recommended in this post (remove gravity dependence in the pressure and add it back as source term in the velocity; see codes shared by flexi182):

https://www.cfd-online.com/Forums/op...ion-issue.html

My problem now is that the water will not stop accelerating. Fluid velocities reach up to abnormally high values. Oddly it does settle to a single value when the viscosity is set really high like 0.1. Maybe I am not understanding something here or maybe steady state cannot really be achieved. Can anyone enlighten me what I'm doing wrong?

Thank you in advance!