Fluid Flow through Porous Media: The Role of Stagnant Zones

We investigate fluid flow through disordered porous media by direct simulation of the Navier-Stokes equations in a two-dimensional percolation structure. We find, in contrast to the log-normal distribution for the local currents found in the analog random resistor network, that over roughly 5 orders of magnitude the distribution nsEd of local kinetic energy E follows a power law, with nsEd ~ E 2a , where a › 0.90 6 0.03 for the entire cluster, while a › 0.64 6 0.05 for fluid flow in the backbone only. Thus the “stagnant” zones play a significant role in transport through porous media, in contrast to the dangling ends for the analogous electrical problem. [S0031-9007(97)04671-1] PACS numbers: 47.55.Mh