Hi All

I am trying to simulate a tank filling from the bottom, valve opening and emptying .

The filling is going fine, but after the opening of the valve, the emptying operation is showing divergence in the k field :

Global Courant Number [Variable Time Step Criteria] : 7.135128

Updating solution at time levels N and N-1.

done.

physical-dt 1.0000e-05

iter continuity x-velocity y-velocity z-velocity k omega vf-water time/iter

reversed flow in 259 faces on pressure-outlet 14.

reversed flow in 259 faces on pressure-outlet 14.

reversed flow in 259 faces on pressure-outlet 14.

reversed flow in 259 faces on pressure-outlet 14.

Stabilizing k to enhance linear solver robustness.

Error: Divergence detected in AMG solver: k

Error: Divergence detected in AMG solver: k

Error Object: #f.

I already tried the turbulence damping, k-epsilon, k-omega, implicit/explicit VOF, reduced time step, options without success.

I reproduce below some pictures of the simulation. Any expert advice *is very welcome.*