Solute dispersion in a variably saturated sand

Modelling multiple solute transport in variably saturated soils

This paper presents two models typical of two different approaches often used for modelling the advective-dispersive transport of multiple ions in variably-saturated porous media. The first approach assumes that all solute reactions can be incorporated directly into the governing transport equations (the one-step method), while the second approach divides the mathematical solution process into ...

Evidence of dispersion in an artificial water-saturated sand sediment.

A laboratory experiment was conducted to measure the speed of sound in an artificial water-saturated granular sediment composed of cleaned and sorted medium-grained sand and degassed distilled water. The experiment was conducted within a range of frequencies where dispersion is predicted by a number of existing models. Between 2 and 4 kHz, the sound speed was inferred from measurements of the r...

Convergent mass conservative schemes for flow and reactive solute transport in variably saturated porous media

Three-dimensional analysis of variably-saturated flow and solute transport in discretely-fractured porous media

A discrete fracture, saturated-unsaturated numerical model is developed where the porous matrix is represented in three dimensions and fractures are represented by two-dimensional planes. This allows a fully three-dimensional description of the fracture network connectivity. Solute advection and diffusion in the porous matrix are also directly accounted for. The variably-saturated flow equation...

Colloid-Facilitated Solute Transport in Variably Saturated Porous Media: Numerical Model and Experimental Verification

Strongly sorbing chemicals (e.g., heavy metals, radionuclides, pharmaceuticals, and explosives) in porous media are associated predominantly with the solid phase, which is commonly assumed to be stationary. However, recent fieldand laboratory-scale observations have shown that in the presence of mobile colloidal particles (e.g., microbes, humic substances, clays, and metal oxides), colloids can...