darcy: Steady state 1-D groundwater flow equation, using Darcy's law

In anchored-inversion/examples.R: Anchored Inversion Client

Description

Solve the 1-D ODE:

\frac{d(K \frac{dh}{dx})}{dx} = s

.

Usage

darcy(K, dx, source = rep(0, length(K)), b0_type = c("dirichlet",
  "neumann"), b0, b1_type = c("dirichlet", "neumann"), b1)

Arguments

K	Hydraulic conductivity (m/s); 1-D vector.
dx	Step size (m) of numerical grid.
source	Volumetric source rate per unit volume; (m^3/s) / {m^3}, ie 1/s.
b0_type	Type of upstream boundary condition.
b0	Value of upstream boundary condition. If b0_type is 'dirichlet', b0 provides a head value (m). If b0_type is 'neumann', b0 provides water flux at boundary. Flux is volumetric rate per volume; same unit as source.
b1_type	Type of downstream boundary condition.
b1	Value of downstream boundary condition.

Details

The model domain is discretized uniformly. K (conductivity), s, h (head) are all evaluated at the model grids.

The possible value range of K is huge (say 13 orders of magnitude). Typical value range for good groundwater conditions is 1e^{-5} to 1e^{-1} m/s.

Value

Steady-state hydraulic head (m) in each grid cell; same length as K.

References

Schwartz and Zhang, Fundamentals of Ground Water, Wiley, 2003.

anchored-inversion/examples.R documentation built on May 12, 2019, 2:39 a.m.