Small-scale models in the form of random walks, combining Gaussian jumps, advection by mean flow field and possibly very long sorbing durations, correspond to experimental data in many porous media, in the laboratory and in the field. Within this frame-work, solutes are observed in two phases,...

Anomalous diffusive transport arises in a large diversity of disordered media. Stochastic formulations in terms of continuous time random walks (CTRW) with transition probability densities presenting spatial and/or time diverging moments were developed to account for anomalous behaviours. Many...

We investigate the influence of a weak uniform bias on chaotic diffusion generated by iterated one-dimensional maps which, in the absence of the bias, lead to subdiffusion.

A Boltzmann-like model for the description of processes of outgassing and contamination is proposed. The cavity /oR2, where the contaminants migrate during their motion from the source region /oR1 to the target /oR3, contains a random medium.

The object of this work is to calculate the effective dielectric constant tensor of a warm plasma made of non point-like ions in an electron gas whose screening length is much larger than the inter-ionic and inter-electronic distances. In this disordered medium, a proper treatment of the...

Morphological models of textures are available to simulate the geometry of two phase composites and to predict their macroscopic physical behaviour: for random mosaics built on a random tessellation, Boolean models, Dead Leaves models, or combinations of these models, third order correlation...

We study the time-dependent potential energy W(t)=U(x(0))−U(x(t)) of a particle diffusing in a one-dimensional random force field (the Sinai model). Using the real space renormalization group method (RSRG), we obtain the exact large time limit of the probability distribution of the scaling...

Intensity correlations between waves reflected and transmitted through random media are analyzed within the framework of the random matrix theory of transport. We introduce a new kind of correlations between transmitted and reflected intensities. For transmitted waves, the spatial correlation...

This paper studies particle propagation in a one-dimensional inhomogeneous medium where the laws of motion are generated by chaotic and deterministic local maps. Assuming that the particle’s initial location is random and uniformly distributed, this dynamical system can be reduced to a random...