Sorbing and non-sorbing solute migration in rough fractures with a multi-species LGA model: Dispersion dependence on retardation and roughness
Titre de la revue : Transport in Porous Media
Volume : 59
N° : 2
Pagination : 175-196
Date de publication : 01/05/2005
A multi-species Lattice-Gas cellular automaton model was applied to the study of the migration of sorbing and non-sorbing tracers in 2D smooth fractures and in a series of increasing roughness fractures. A tenfold increase of the dispersion of the non-sorbing tracer was calculated in the highest roughness case compared to the smooth fracture. Up to a threefold increase of the dispersion of the sorbing tracers was calculated compared to the non-sorbing tracer. These enhanced dispersions were found to be of a Fickian form and were interpreted in terms of the classical Taylor–Aris dispersion. The effects of roughness and retardation over the increase of dispersion were identified and quantified through a semi-empirical relation. These effects were found additive and independent.