phreatic conductivity scaling

Hi, I am re-posting this question as a new topic...

Am I correct in my understanding that in the phreatic mode the overall conductivity, including that in the z-direction, is scaled by the saturation or, at a minimum, the residual water depth?

I have had the experience that recharge (applied as inflow) seems to become trapped at the top of the aquifer if the layers below are dry, resulting in unrealistically high (10e8!) heads, and that this would occur if Kz were similarly scaled. 

The same model run in confined mode results in realistic head values.

Thanks!
Milos

Yes, you are correct with this. All conductivities are scaled by saturation, also in vertical direction. Therefore it can happen that recharge mounds in the top slice. A practical way to deal with that would be to increase the residual water level in the dry layers.

Hi,
I think my question fits here.
I am modelling a simple seepage face in the side of a hillslope (simple rectangle problem).  I have unspecified (i.e. default no-flow) boundaries in the upslope and lateral boundaries, constant head at the downgradient boundary.  Top slice is free and moveable and has a specified flux with a ground surface constraint.  The model is working well, except I get some groundwater mounding in the area of groundwater recharge, which I think is causing my water balance to show a net inflow.  Any suggestions ?     
Laurie

The specific issue discussed above should not be present in the free and moveable mesh solution, it is specific to the phreatic and unsaturated solution.

Though in the same principle, the model is probably mounding water because the system requires a higher gradient to transmit the recharge specified.  If you are using the free and moveable mesh then this suggests that the model is uncalibrated because recharge is too high or conductivity is too low or constant head too high.

HOWEVER...there are some issues specific to FEFLOW where constrained boundary conditions will 'flip' and change type when the constraint is not satisfied.

I can't speak to your 'net inflow' issue.