shypFun.01210 {spsh}

van Genuchten-Mualem bimodal Soil Hydraulic Propterty Model

Description

bimodal van Genuchten-Mualem functions (Durner model) for the retention and hydraulic conductivity curves (Durner 1994).

Usage

shypFun.01210(p, h)

Arguments

p

vector of the 9 van Genuchten-Mualem model parameters, order is sensitve and has to be given as:

thr	residual water water content [cm cm-3]
ths	saturated water water content [cm cm-3]
alf1	van Genuchten alpha [cm-3]
n1	van Genuchten n [-]
w1	fraction of the first modality [-], w2 is internally computed as w2 = 1-w1
alf2	van Genuchten alpha of the second modality[cm-3]
n2	van Genuchten n of the second modality [-]
Ks	saturated conductivity [cm d-1]
tau	exponent of Se in the capillary conductivity model, sometimes denoted in the literature as l [-]

h

pressure heads [cm] for which the corresponding retention and conductivity values are calculated.

Details

The function solves analytically the spec. water capacity function and integral to the capillary bundle model.

Value

returns a list with calculations at specified h:

theta

calculated volumetric moisture content

Se

calculated saturation

cap

specific water capacity function

psd

pore size distribution

Kh

Hydraulic conductivity values

Author(s)

Tobias KD Weber , [e-mail]

References

Durner W (1994). “Hydraulic conductivity estimation for soils with heterogeneous pore structure.” Water Resources Research, 30(2), 211–223. ISSN 0043-1397.

Examples

p <- c("thr" = 0.1, "ths" = 0.4, alf1 = 0.5, "n1" = 3,
       "w1" = .6, "alf2" = 0.01, "n2" = 1.6, 
       "Ks" = 100, "tau" = .5)
h <- 10^seq(-2, 6.8, length = 197)
shyp.L <- shypFun.01210(p, h)