Finite Element Techniques for Fluid Flow

FLOW THROUGH POROUS MEDIA 221

for all x

1

values. Once this state is reached, a new solution for the φ

potential can be computed using the finite element mesh which has

now to be vertically displaced in order to fit the new phreatic

surface.

For the problem shown in Figure 6.8(a), a total of

421

nodes and

702 three node triangular elements were used.

2

Three different cases were solved

:

1 The porous medium was treated as isotropic,

K

ll

/K

22

= 1

2 The medium was treated as orthotropic with

K

11

/K

22

= y

3 It was taken to be orthotropic with

K

ll

/K

22

= 3

Figure 6.8(b) shows the free surface for different times for the

above

cases.

The time was mad ...