Premium
Correspondence of Hydraulic Functions for Unsaturated Soils
Author(s) -
Warrick A. W.
Publication year - 1995
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj1995.03615995005900020003x
Subject(s) - sorptivity , infiltrometer , zeroth law of thermodynamics , soil water , mathematics , moment (physics) , context (archaeology) , thermal diffusivity , infiltration (hvac) , soil science , hydraulic conductivity , mathematical analysis , thermodynamics , environmental science , geology , physics , compressive strength , paleontology , classical mechanics
This study investigated the correspondence of hydraulic functions for unsaturated soils. The overall idea was to identify general properties and explore conditions for which alternative functions give the same or similar responses. Five commonly used empirical forms were examined in this context. The objective was to extend solutions based on particular forms of hydraulic models to more general conditions. For example, the commonly applied formula for steady‐state flow of a disk infiltrometer assumes a quasi‐linear form of Richards' equation. Another area of application is parameter identification and the choice of alternative models. In order for two sets of models to correspond, the zeroth and first moments of the soil water diffusivity, D , should be equal for the respective models. The zeroth moment is simply the integral of D with respect to water content across the range of interest and is closely related to sorptivity and capillary length. The first moment characterizes the shape of D .