Hostname: page-component-76fb5796d-wq484 Total loading time: 0 Render date: 2024-04-25T13:53:12.163Z Has data issue: false hasContentIssue false

Hydrodynamic diffusion of suspended particles: a symposium

Published online by Cambridge University Press:  26 April 2006

Robert H. Davis
Affiliation:
University of Colorado, Boulder, CO 80309-0424, USA

Abstract

Hydrodynamic diffusion refers to the fluctuating motion of non-Brownian particles (or droplets or bubbles) in a dispersion, which occurs due to multiparticle interactions. For example, in a concentrated sheared suspension, particles do not move along streamlines but instead exhibit fluctuating motions as they tumble around each other (figure 1a). This leads to a net migration of particles down gradients in particle concentration and in shear rate, due to the higher frequency of encounters of a test particle with other particles on the side of the test particle which has higher concentration or shear rate. As another example, suspended particles subject to sedimentation or fluidization do not generally move relative to the fluid with a constant velocity, but instead experience diffusion-like fluctuations in velocity due to interactions with neighbouring particles and the resulting variation in the microstructure or configuration of the suspended particles (figure 1b). In flowing granular materials, the particles interact through direct collisions or contacts; these collisions also cause the particles to undergo fluctuating motions characteristic of diffusion processes. Although the existence and importance of hydrodynamic diffusion of particles have been embraced only in the past several years, the subject has already captured the attention of a growing number of researchers in several diverse fields (e.g. suspension mechanics, fluidization, materials processing, and granular flows).

Type
Research Article
Copyright
© 1996 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

Abbott, J. R., Tetlow, N., Graham, A. L., Altobelli, S. A., Fukushima, E., Mondy, L. A. & Stephens, T. S. 1991 Experimental observations of particle migration in concentrated suspensions: Couette flow. J. Rheol. 35, 773795.Google Scholar
Acrivos, A., Batchelor, G. K., Hinch, E. J., Koch, D. L. & Mauri, R. 1992 Longitudinal shear-induced diffusion of spheres in a dilute suspension. J. Fluid Mech. 240, 651657.Google Scholar
Acrivos, A., Mauri, R. & Fan, X. 1993 Shear-induced resuspension in a Couette device. Intl J. Multiphase Flow 19, 797802.Google Scholar
Brady, J. F. & Bossis, G. 1988 Stokesian dynamics. Ann. Rev. Fluid Mech. 20, 111157.Google Scholar
Buggisch, H. & Louffelmann, G. 1989 Theoretical and experimental investigation into local granulate mixing mechanisms. Chem. Engng Prog. 26, 193200.Google Scholar
Caflisch, R. E. & Luke, J. H. C. 1985 Variance in the sedimentation speed of a suspension. Phys. Fluids 28, 750760.Google Scholar
Campbell, C. S. 1990 Rapid granular flows. Ann. Rev. Fluid Mech. 22, 5792.Google Scholar
Da Cunha, F. R., & Hinch, E. J. 1996 Shear-induced dispersion in a dilute suspension of rough spheres. J. Fluid Mech. 309, 211223.Google Scholar
Davis, R. H. 1992 Effects of surface roughness on a sphere sedimenting through a dilute suspension of neutrally buoyant spheres. Phys. Fluids A 4, 26072619.Google Scholar
Davis, R. H. & Hassen, M. A. 1988 Spreading of the interface at the top of a slightly polydisperse sedimenting suspension. J. Fluid Mech. 196, 107134.Google Scholar
Davis, R. H. & Hill, N. A. 1992 Hydrodynamic diffusion of a sphere sedimenting through a dilute suspension of neutrally-buoyant spheres. J. Fluid Mech. 236, 513533.Google Scholar
Davis, R. H., Serayssol, J.-M. & Hinch, E. J. 1986 The elastohydrodynamic collision of two spheres. J. Fluid Mech. 163, 479492.Google Scholar
Evans, A. R., Shaqfeh, E. S. G. & Frattini, P. L. 1994 Observations of polymer conformation during flow through a fixed fiber bed. J. Fluid Mech. 281, 319356.Google Scholar
Frattini, P. L., Shaqfeh, E. S. G., Levy, J. L. & Koch, D. L. 1991 Observations of axisymmetric tracer particle orientation during flow through a dilute fixed bed of fibers. Phys. Fluids A 3, 25162528.Google Scholar
Graham, A. L., Altobelli, S. A., Fukushima, E., Mondy, L. A. & Stephens, T. S. 1991 Note: NMR imaging of shear-induced diffusion and structure in concentrated suspensions undergoing Couette flow. J. Rheol. 35, 191201.Google Scholar
Harlen, O. G. & Koch, D. L. 1992 Extensional flow of a suspension of fibers in a dilute polymer solution. Phys. Fluids A 4, 10701073.Google Scholar
Harlen, O. G. & Koch, D. L. 1993 Simple shear flow of a suspension of fibres in a dilute polymer solution of high Deborah number. J. Fluid Mech. 252, 187207.Google Scholar
Hinch, E. J. 1988 Sedimentation of small particles. In Disorder and Mixing (ed. E. Guyon, J.-P. Nadal & Y. Pomeau), p. 153. Kluwer.
Hsiau, S. S. & Hunt, M. L. 1993 Kinetic theory analysis of flow-induced particle diffusion and thermal conduction in granular material flows. Trans. ASME C: J. Heat Transfer 115, 541548.Google Scholar
Jenkins, J. T. & Mancini, F. 1989 Kinetic theory for binary mixtures of smooth, nearly elastic spheres. Phys. Fluids A 1, 20502057.Google Scholar
Jenkins, J. T. & Savage, S. B. 1983 A theory for the rapid flow of identical smooth, nearly elastic, spherical particles. J. Fluid Mech. 130, 187207.Google Scholar
Kapoor, B. & Acrivos, A. 1995 Sedimentation and sediment flow in settling tanks with inclined walls. J. Fluid Mech. 290, 3966.Google Scholar
Karnis, A., Goldsmith, H. L. & Mason, S. G. 1966 The kinetics of flowing dispersions, I. Concentrated suspensions of rigid particles. J. Colloid Interface Sci. 22, 531553.Google Scholar
Koch, D. L. 1990 Kinetic theory for a monodisperse gas-solid suspension. Phys. Fluids A 2, 17111723.Google Scholar
Koch, D. L. 1992 Anomalous diffusion of momentum in a dilute gas-solid suspension. Phys. Fluids A 4, 13371346.Google Scholar
Koch, D. & Shaqfeh, E. S. G. 1991 Screening in sedimenting suspensions. J. Fluid Mech. 224, 275303.Google Scholar
Koh, C. J., Hookham, P. & Leal, L. G. 1994 An experimental investigation of concentrated suspension flows in a rectangular channel. J. Fluid Mech. 266, 131.Google Scholar
Ladd, A. J. C. 1993 Dynamical simulations of sedimenting spheres. Phys. Fluids A 5, 299310.Google Scholar
Ladd, A. J. C. 1994a Numerical simulations of particulate suspensions via a discretized Boltzmann equation. Part 1. Theoretical foundation. J. Fluid Mech. 271, 285310.Google Scholar
Ladd, A. J. C. 1994b Numerical simulations of particulate suspensions via a discretized Boltzmann equation. Part 2. Numerical results. J. Fluid Mech. 271, 311339.Google Scholar
Lee, S., Yang, Y., Choi, C. & Lee, T. 1992 Combined effect of sedimentation velocity fluctuation and self-sharpening on interface broadening. Phys. Fluids A 4, 26012606.Google Scholar
Leighton, D. & Acrivos, A. 1986 Viscous resuspension. Chem. Engng Sci. 41, 13771384.Google Scholar
Leighton, D. T., & Acrivos, A. 1987a Measurement of shear-induced self-diffusion in concentrated suspensions of spheres. J. Fluid Mech. 177, 109131.Google Scholar
Leighton, D., & Acrivos, A. 1987b The shear-induced migration of particles in concentrated suspensions. J. Fluid Mech. 181, 415439.Google Scholar
Martin, J., Rakotomalala, N. & Salin, D. 1994 Hydrodynamic dispersion broadening of a sedimentation front. Phys. Fluids 6, 32153217.Google Scholar
Martin, J., Rakotomalala, N. & Salin, D. 1995 Hydrodynamic dispersion of noncolloidal suspensions: Measurement from Einstein's argument. Phys. Rev. Lett. 74, 13471350.Google Scholar
Mondy, L. A.Graham, A. L. & Jensen, J. L. 1986 Continuum approximations and particle interactions in concentrated suspensions. J. Rheol. 30, 10311051.Google Scholar
Nakagawa, M. 1994 Axial segregation of granular flows in a horizontal rotating cylinder. Chem. Engng Sci. 49, 25402544.Google Scholar
Nakagawa, M., Altobelli, S. A., Caprihan, A., Fukushima, E. & Jeong, E. K. 1993 Non-invasive measurements of granular flows by magnetic resonance imaging. Exps. Fluids 16, 5460.Google Scholar
Nicolai, H. & Guazzelli, E. 1995 Effect of the vessel size on the hydrodynamic diffusion of sedimenting spheres. Phys. Fluids 7, 35.Google Scholar
Nicolai, H., Herzhaft, B., Hinch, E. J., Oger, L. & Guazzelli E. 1995 Particle velocity fluctuations and hydrodynamic self-diffusion of sedimenting non-Brownian spheres. Phys. Fluids 7, 1223.Google Scholar
Nir, A. & Acrivos, A. 1990 Sedimentation and sediment flow on inclined surfaces. J. Fluid Mech. 212, 139153.Google Scholar
Nott, P. R. & Brady, J. R. 1994 Pressure-driven flow of suspensions: simulation and theory. J. Fluid Mech. 275, 157199.Google Scholar
Peciar, M., Buggisch, H. & Renner, M. 1994 Experimental investigation into the influence of the particle size distribution upon the local mixing mechanisms in a flowing bulk material. Chem. Engng Prog. 33, 3950.Google Scholar
Phillips, R. J., Armstrong, R. C., Brown, R. A., Graham, A. L. & Abbott, J. R. 1992 A constitutive equation for concentrated suspensions that accounts for shear-induced particle migration. Phys. Fluids A 4, 3040.Google Scholar
Rahnama, M., Koch, D. L. & Shaqfeh, E. S. G. 1995 The effect of hydrodynamic interactions on the concentration distribution of fiber suspensions subject to simple shear flow. Phys. Fluids A 7, 487506.Google Scholar
Sangani, A. S. & Mo, G. 1995 An O(N) algorithm for Stokes and Laplace interactions of particles. In preparation for submission to Phys. Fluids.
Savage, S. B. & Dai, R. 1993 Studies of granular shear flows. Wall slip velocities, layering, and self-diffusion. Mech. Mater. 16, 225238.Google Scholar
Schaflinger, U., Acrivos, A. & Zhang, K. 1990 Viscous resuspension of a sedimentation within a laminar and stratified flow. Intl J. Multiphase Flow 16, 567578.Google Scholar
Shaqfeh, E. S. G. & Koch, D. L. 1988 The effects of hydrodynamic interactions on the orientation of axisymmetric particles flowing through a fixed bed of spheres or fibers. Phys. Fluids 31, 728743.Google Scholar
Shaqfeh, E. S. G. & Koch, D. L. 1990 Orientational dispersion of fibers in extensional flows. Phys. Fluids A 2, 10771093.Google Scholar
Shaqfeh, E. S. G. & Koch, D. L. 1992 Polymer stretch in dilute fixed beds of spheres or fibres. J. Fluid Mech. 224, 1754.Google Scholar