open TELEMAC-MASCARET The mathematically superior suite of solvers

Hi all,

I have some problems with the modelling of the free surface using Telemac3d. We have a physical model of a reservoir in our lab and I have the water levels measured there. I also have measured water levels from a flood event in 2005 (the bed levels in the physical model correspond to the bed levels after the flood 2005).
The reservoir has an old weir without spilling basin. I implemented this weir fully (geometry and mesh) in the numerical model. The pillars of the weir are like the pillars of a bridge in the model (see picture of the geometry).

Now my problem: The water levels calculated with 2D match very well (constant viscosity 0,5; kst 50), but in 3D I get much higher water levels before the weir (in flow direction). I changed the turbulence model form k-e to cv and prandtl, but the tendency is the same (still 0.5 m too high).

In the next step I would like to start the sediment transport calculations, but with the high water levels in 3D I am forced to stay with 2D, which is not my favourite option….

Does anybody (or JMH..) has a hint for me?
Many thanks,
Gabriele

My second picture is missing in the previous post
so there is the geometry of the weir