Hi,
I'm working on a 3D regional model. I got some trouble to reach the default convergent criterion when I'm running the model. So, I tried different strategies :
1) I converge perfectly when I put the boundary conditions only on the first layer (Constant head) and this way make perfect sense. The problem is that I have in incorrect mass balance. I mean, there is no imbalance, but the flow rate that coming from the boundaries is too high in proportion with the recharge...and here is the problem. It's not normal to get ''artificial'' water from the boundaries.
2) If I copy the constant head on the second layer, I cannot reach the convergence criterion, but the mass balance is ok....it drops by 4 order of magnitude.
The result with these two simulations is very different in some region. So which one is the best ? Should we prefer to reach the convergence or should we prefer to get a correct mass balance ? Some other suggestions or way to solve it are welcome.
Thanks
Michael
