Journal ArticleDOI
A dual-porosity model for simulating the preferential movement of water and solutes in structured porous media
TLDR
In this paper, a dual-porosity model was developed for the purpose of studying variably saturated water flow and solute transport in structured soils or fractured rocks, where water in both pore systems is assumed to be mobile.Abstract:
A one-dimensional dual-porosity model has been developed for the purpose of studying variably saturated water flow and solute transport in structured soils or fractured rocks. The model involves two overlaying continua at the macroscopic level: a macropore or fracture pore system and a less permeable matrix pore system. Water in both pore systems is assumed to be mobile. Variably saturated water flow in the matrix as well as in the fracture pore system is described with the Richards' equation, and solute transport is described with the convection-dispersion equation. Transfer of water and solutes between the two pore regions is simulated by means of first-order rate equations. The mass transfer term for solute transport includes both convective and diffusive components. The formulation leads to two coupled systems of nonlinear partial differential equations which were solved numerically using the Galerkin finite element method. Simulation results demonstrate the complicated nature of solute leaching in structured, unsaturated porous media during transient water flow. Sensitivity studies show the importance of having accurate estimates of the hydraulic conductivity near the surface of soil aggregates or rock matrix blocks. The proposed model is capable of simulating preferential flow situations using parameters which can be related to physical and chemical properties of the medium.read more
Citations
More filters
Journal ArticleDOI
A review of non-equilibrium water flow and solute transport in soil macropores: principles, controlling factors and consequences for water quality
TL;DR: The potential for non-equilibrium water flow and solute transport at any site depends on the nature of the macropore network, which is determined by the factors of structure formation and degradation as mentioned in this paper.
Journal ArticleDOI
Development and Applications of the HYDRUS and STANMOD Software Packages and Related Codes
TL;DR: A review of the history of development, main processes involved, and selected applications of HYDRUS and related models and software packages developed collaboratively by several groups in the United States, the Czech Republic, Israel, Belgium, and the Netherlands can be found in this paper.
Journal ArticleDOI
Hydraulic conductivity estimation for soils with heterogeneous pore structure
TL;DR: In this paper, a flexible θ(ψ) function was formed by superimposing unimodal retention curves of the van Genuchten (1980) type with the conductivity prediction model of Mualem (1976).
Journal ArticleDOI
Review and comparison of models for describing non-equilibrium and preferential flow and transport in the vadose zone
TL;DR: In this paper, a review of existing approaches for modeling preferential and non-equilibrium flow and transport in the vadose zone is presented, which range from relatively simplistic models to more complex physically based dual-porosity, dual-permeability, and multi-region type models.
Journal ArticleDOI
Recent Developments and Applications of the HYDRUS Computer Software Packages
TL;DR: Review of selected capabilities of HYDRUS implemented since 2008 New standard and nonstandard specialized add‐on modules significantly expanded capabilities of the software.
References
More filters
Journal ArticleDOI
A closed-form equation for predicting the hydraulic conductivity of unsaturated soils
van Genuchten,M. Th. +1 more
TL;DR: Van Genuchten et al. as mentioned in this paper proposed a closed-form analytical expression for predicting the hydraulic conductivity of unsaturated soils based on the Mualem theory, which can be used to predict the unsaturated hydraulic flow and mass transport in unsaturated zone.
Journal ArticleDOI
The Behavior of Naturally Fractured Reservoirs
J.E. Warren,P.J. Root +1 more
TL;DR: Enginsera et al. as discussed by the authors proposed an idealized model for the purpose of studying the characteristic behavior of a permeable medium which contains regions which contribute significantly to the pore volume of the system but contribute negligibly to the flow capacity.
Journal ArticleDOI
Basic concepts in the theory of seepage of homogeneous liquids in fissured rocks [strata]
Journal ArticleDOI
Macropores and water flow in soils
Keith Beven,Peter F. Germann +1 more
TL;DR: In this article, the importance of large continuous openings (macropores) on water flow in soils is discussed and the limitations of models that treat macropores and matrix porosity as separate flow domains are stressed.
Journal ArticleDOI
Mass transfer studies in sorbing porous media. I. Analytical solutions
TL;DR: An analytical solution for the movement of chemicals through a sorbing porous medium with lateral or intra-aggregate diffusion is presented in this paper, where the liquid phase in the porous medium is divided into mobile and immobile regions.
Related Papers (5)
A closed-form equation for predicting the hydraulic conductivity of unsaturated soils
van Genuchten,M. Th. +1 more