Table of Contents
Advertisement
Theoretical basics
9.3.1
The van Genuchten/Mualem modell
With this model the effective saturation
the unsaturated conductivity K in relation to the matric potential h are
predetermined by the following equation formula (van Genuchten,
1980):
K
(
h
)
K
Here the residual water content
, the inverse value of the bubble point potential
s
pore size distribution
function. Furthermore, the tortuosity parameter
saturated conductivity
9.3.2
The bimodal van Genuchten/Mualem Model
This model suggested by Durner (1994) describes the retention and
conductivity function by overlapping of two individual van Genuchten-
functions (Priesack and Durner, 2006).
2
K
(
h
)
=
K
w
[1
s
j
j
1 =
The j are indexes for the parameters of each van Genuchten
function, and
w
following restriction applies:
S
(
h
)
1 (
e
n
(
/ 1
n
1 (
(
h
)
)
s
[-] are the fitting parameters for the retention
n
are fitted to get the conductivity function.
K
s
2
S
(
h
)
1 (
e
j
j
1
j n
/ 1
n
1
(
h
)
]
j
j
are the weights of both partial functions. The
j
0
w
73/92
S
e
n
/ 1
n
1
(
h
)
)
) 1
n
1
1
(
h
)
1
, the water content at saturation
r
n
/ 1
n
1
(
h
)
j
)
j
j
2
w
{1
(
h
j
j
j
j
1 =
2
j
1 =
and
1
w
j
j
and
r
s
r
2
/ 1
n
1
n
(
h
)
-1
[cm
] and the
[-] and the
j n
1
j n
/ 1
)
[1
(
h
)
]
j
w
j
j
.
1
2
n
1
j
}
,
Advertisement
Table of Contents
