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Hi,
I'm quite new to Feflow, had one indroductory courses, but that's it...

I'd like to model a hydrogeological problem consisting of 4 unconfined aquifers.
Flow direction of the top aquifers 1 and 2 is NE with a gradient of 0,1.
Flow direction of the lower aquifers 3 and 4 is WSW with a gradient of 0,01.
Number of layers: 57

Simpliefied crosssection, every element consits of multiple layers:

Partially saturated topsoil
Top aquifer 1
Bottom aquifer 1
Aquitard
Partially saturated soil
Top aquifer 2
Bottom aquifer 2
Aquitard
Partially saturated soil
Top aquifer 3
Bottom aquifer 3
Aquitard
Partially saturated soil
Top aquifer 4
Base of model

I assume it is best to design the superelement to be a parallelogram, so its sides are perpendicular to the two flow directions?

I have two problems:

1) How do I have to set the "Free surfaces" for the unconfined aquifers?
Is this correct:

Partially saturated topsoil --> Unspecified
Top aquifer 1 layer --> Phreatic
Aquifer 1 layers --> Unspecified
Aquitard layers --> Fixed
Partially saturated soil layers --> Unspecified
Top aquifer 2 layer --> Phreatic
Aquifer 2 layers --> Unspecified
Aquitard layers--> Fixed
Partially saturated soil layers --> Unspecified
Top aquifer 3 layer --> Phreatic
Aquifer 3 layers --> Unspecified
Aquitard layers --> Fixed
Partially saturated soil layers --> Unspecified
Top aquifer 4 layer --> Phreatic
Aquifer 4 layers --> Unspecified
Base of model --> Fixed

2) How do I have to set the 1 kind hydraulic head boundary conditions, so that the different flow direction are considered?

Thank you
Philipp