Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-19T01:58:01.892Z Has data issue: false hasContentIssue false

The effect of order on dispersion in porous media

Published online by Cambridge University Press:  26 April 2006

Donald L. Koch
Affiliation:
School of Chemical Engineering, Cornell University, Ithaca, NY 14853
Raymond G. Cox
Affiliation:
Department of Civil Engineering and Applied Mechanics, McGill University, 3480 University Street, Montreal, Quebec H3A 2A7, Canada
Howard Brenner
Affiliation:
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
John F. Brady
Affiliation:
Department of Chemical Engineering, California Institute of Technology, Pasadena, CA 91125

Abstract

The effect of spatial periodicity in grain structure on the average transport properties resulting from flow through porous media are derived from the basic conservation equations. At high Péclet number, the mechanical dispersion that is induced by the stochastic fluid velocity field in disordered media and is independent of the molecular diffusivity is absent in periodic media where the velocity field is deterministic. Instead, the fluid motion enhances diffusion by an amount proportional to U2l2/D when the bulk flow is in certain directions (of which there are an infinite number), and to D otherwise. The non-mechanical dispersion mechanisms associated with the zero velocity of the fixed grains is qualitatively similar in ordered and disordered media.

Type
Research Article
Copyright
© 1989 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Aref, H.: 1984 Stirring by chaotic advection. J. Fluid Mech. 143, 121.Google Scholar
Brenner, H.: 1980 Dispersion resulting from flow through spatially periodic porous media. Phil. Trans. R. Soc. Lond. A297, 81133.Google Scholar
Brenner, H. & Adler, P. M., 1982 Dispersion resulting from flow through spatially periodic porous media: II. Surface and intraparticle transport. Phil. Trans. R. Soc. Lond. A307, 149200.Google Scholar
Eidsath, A., Carbonell, R. G., Whitaker, S. & Herrman, L. R., 1983 Dispersion in pulsed systems – III: comparison between theory and experiments for packed beds. Chem. Engng Sci. 38, 18031816.Google Scholar
Gunn, D. J. & Pryce, C., 1969 Dispersion in packed beds. Trans. Inst. Chem. Engrs 47, T341T350.Google Scholar
Hasimoto, H.: 1959 On the periodic fundamental solutions of the Stokes equations and their application to viscous flow past a cubic array of spheres. J. Fluid Mech. 5, 317328.Google Scholar
Koch, D. L.: 1986 Dispersion in heterogeneous media. Ph.d. thesis, Massachusetts Institute of Technology.
Koch, D. L. & Brady, J. F., 1985 Dispersion in fixed beds. J. Fluid Mech. 154, 399427.Google Scholar
Koch, D. L. & Brady, J. F., 1987 The symmetry properties of the effective diffusivity in anisotropic porous media. Phys. Fluids 30, 642650.Google Scholar
Perrins, W. T., Mckenzie, D. R. & Mcphedran, R. C., 1979 Transport properties of regular arrays of cylinders. Proc. R. Soc. Lond. A369, 207225.Google Scholar
Sangani, A. S. & Acrivos, A., 1983 The effective conductivity of a periodic array of spheres. Proc. R. Soc. Lond. A386, 263275.Google Scholar
Stewart, G. W.: 1973 Introduction to Matrix Computations. Academic.
Rayleigh, Lord: 1892 On the influence of obstacles arranged in rectangular order upon the properties of a medium. Phil. Mag. 34, 481502.Google Scholar