Abstract: The dispersion process in porous media is analysed and simulated by use of the random simulation method in this paper. Anomalous dispersion and the preferential path for dispersion flow are found near a percolation threshold caused by random pore removal or blockage. The calculated results show that the longitudinal dispersivity is greater when it is near a percolation threshold than in Euclidean space.

Key words: random simulation, anomalous dispersion, porous media, percolation theory