[JanZ]

Dear all,

I am pretty new to CFD and new to this forum. I took over CFD work of a colleague of mine about three months ago.

We are using LTSInterFoam to study ship flow and reached a pretty good setup for the calculations. But with one of the latest calculations, I discovered a slight water level rise at the start of the domain (and spreads across the whole domain), which seems unphysical, because of two reasons (I think):

- The rise of the water level starts way too early
- and the water level rises uniformly across the width of the domain.

I attached some pictures of the problem and noticed two things:

- The velocity profile is a bit strange at the start of the domain: why is the velocity changing in this way? At the start, it should remain pretty much the inlet velocity (which is set at 1.85166 m/s) I think.
- In this region, there are some non-orthogonal cells/faces.
- I don't know why these are marked as non-orthogonal?
- Could these cause such a water level rise?

I think it has something to do with either the non-ortho faces or boundary conditions.

I would appreciate it when anyone has any suggestions on the causes and possible solutions for this problem.

Thanks in advance,
JanZ