net.simplace.sim.components.soil.hillflow.VanGenuchtenFormulas

Soil water retention functions according to Van Genuchten (1980) Code extracted from the HillFlow1D model. '''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, 892-898.

public final class VanGenuchtenFormulas {
// Public Constructors
public VanGenuchtenFormulas();

// Class Methods

public static double genuk(double h, double m, double n, double alpha);

Calculates conductivity from water potential

h Water pressure head (negative)
m Constant
n Constant
alpha Constant

returns Conductivity at pressure h

public static double genup(double ts, double ta, double tr, double m, double
n, double alpha);

Calculates water pressure from water content

ts Saturated soil water content theta(s) (volumetric)
ta Actual soil water content theta (volumetric)
tr Residual soil water content theta(r) (volumetric)
m Constant
n Constant
alpha Constant

returns Water pressure head h (negative)

public static double genuth(double ts, double h, double tr, double m, double
n, double alpha);

Calculates water content from water pressure potential

ts Saturated soil water content theta(s) (volumetric)
h Water pressure head (negative)
tr Residual soil water content theta(r) (volumetric)
m Constant
n Constant
alpha Constant

returns Water content theta at pressure h (volumetric)

}