Fractures predicting solute transport

PREDICTING SOLUTE TRANSPORT IN FRACTURED ROCKS- PROCESSES, MODELS AND SOME CONCERNS... 

A final consideration is how parameters from geometrical models might be incorporated into models to better predict solute dispersion at the macroscopic scale. One approach involves the development of effective continuum models for structured soils and fractured rocks (de Josselin de Jong Way, 1972 Long et al., 1982 Berkowitz et al., 1988). Another approach is the inclusion of dispersion due to porosity variations in Monte Carlo simulations of solute transport in random conductivity fields (Fiori, 1998 Hassan et al., 1998). It is also possible to embed geometrical models within multiregion velocity based models (Gwo et al., 1998). 

Shikaze, S.G., E.A. Sudicky, and F.W. Schwartz. 1998. Density-dependent solute transport in discretely-fractured geologic media Is prediction possible J. Contam. Hydrol. 34 273-291. 

Natural systems rarely contain perfectly uniform, regular voids. A regular shape model may be unrealistic for macropores and fractures with irregular walls. Thus, it is useful to examine the impact of systematic variations in channel diameter on solute dispersion. Variable shape models are attractive for simulating pore scale dispersion because a single unit cell is often able to capture a wide range of transport processes, from convection in the center of the channel to diffusion in backwater zones near the apex (see Fig. 3-2B). Furthermore, the macroscopic behavior of such models can be predicted from well-defined geometric parameters. 

---