Sat {SoilHyP}

Capillary saturation function

Description

Capillary saturation function of van Genuchten (unimodal or bimodal pore space distributions) and Brooks and Corey (unimodal pore space distribution).

Usage

Sat(suc, par.shp, modality = c("uni"), FUN.shp = "vg", suc.negativ = TRUE)

Arguments

suc

Suction/pressure heads. Negative if suc.negativ = TRUE

par.shp

named parameter in list or vector

modality

pore size distribution ('uni' or 'bi')

FUN.shp

Funktion for soil hydraulic properties (vG or bc) (see details)

suc.negativ

set TRUE if suction/pressure heads are negative and FALSE if positive

Details

FUN.shp:

vG: van Genuchten (uni or bimodal) (vGM is working aswell)
bc: Brooks and Corey (uni)

par.shp (van Genuchten):

alfa [1/L]: van Genuchten shape parameter
n [-]: van Genuchten shape parameter
m [-]: shape parameter (m = 1-(1/n) if missing)

par.shp (additional for bimodal (modality = 'bi')):

w2 [-]: weigthing between pore space distribution
alfa2 [1/L]: van Genuchten parameter alfa for second pore space distribution
n2 [-]: van Genuchten parameter n for second pore space distribution

par.shp (Brooks and Corey):

alfa [1/L]: inverse of the air-entry value or bubbling pressure
lambda [-]: pore size distribution index

References

Van Genuchten, M. T. (1980). A closed-form equation for predicting the hydraulic conductivity of unsaturated soils. Soil science society of America journal, 44(5), 892-898.

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

Brooks, R.H., and A.T. Corey (1964): Hydraulic properties of porous media. Hydrol. Paper 3. Colorado State Univ., Fort Collins, CO, USA.