Solute transport in single and multiple scale heterogeneous formations: Numerical experiments

The heterogeneity of natural formations has a significant impact on the spreading characteristics of groundwater contaminants. This study focuses on the influence of different geological settings and characterization methods on transport characteristics in heterogeneous porous formations. Several patterns of geological structures have been synthesized by different techniques and then the two dimensional form of flow and solute transport equations are solved numerically in these structures. The generated fields considered in these experiments are stationary Gaussian fields, Markovian fields developed by [Elfeki, Uffink and Barends, 1995] and combiend random fields (Gaussian-Markovian fields). From the experiments, one may distinguish two transport regimes: Fickian regime and non-Fickian (Anomalous) regime. The non-Fickian regimes can be divided into superdiffusive dispersion, in which, the growth of longitudinal variance of particles cloud with time is faster than linearity, or subdiffusive dispersion, in which, the growth of longitudinal variance of particles cloud is slower than linearity.