The EI library in London is temporarily closed, as a precautionary measure in light of the ongoing COVID-19 situation. The Knowledge Service will still be answering email queries via, and is available for live chats on this page during working hours (09:15-17:00 GMT). Our e-library is always open for members here:, for full-text access to over 200 e-books and millions of articles. We are sorry for any inconvenience.

Some remarkable observations of laboratory dispersion using computed tomography (CT). M.P. Walsh and E.M. Withjack. J. Can. Petrol. Technol., November 1994, 33(9), 36--44.

Fickian dispersion models are described for use in analysing undirectional, equal-viscosity, equal-density laboratory displacement tests. The technique is illustrated in mathematical terms. A permeability-variation dispersion model and a permeability-variation-plus-Fickian dispersion model are explained. Effects of system length, permeability variation, and scale-dependent dispersivities are discussed. Test results in Berea sandstone cores lead to new conclusions about flow in porous media. Mathematical modelling confirms that non-Fickian flow behaviour can be attributed to small but significant spatial permeability variations. New dispersion models are proposed for the analysis of dispersive flows. 28 refs.

Abstract details

Please login to save this item