University of Illinois at Urbana-Champaign. Water Resources Center
Abstract
Increased utilization of non-dilute, solid-fluid suspensions in transporting materials and in estimating the distribution of particles from atmospheric fallout, demands that the basic fluid-particle interactions be thoroughly understood. Our previous studies of such interactions were conducted on only dilute suspensions, whereas this study has been conducted in the same vertical flows but with solid spherical particle suspensions with concentrations, ɸ, from O to 10 percent by volume, a range of practical interest to sedimentation and erosion as well as in slurry pipelines. Detailed experimental results of the particle-fluid relative mean and rms velocities as well as particle dispersion were obtained for two particle densities and several ɸ values. Both particle types showed a rapid rise of both relative mean and rms velocities as ɸ increased to about 1-2 percent and fell off gradually for higher ɸ values. Dispersion followed a similar behavior. The higher free fall velocity particles exhibited larger rms velocities and increased dispersion from the lighter, lower free fall velocity particles. Analytical models of the ɸ-dependence showed good agreement with the data, suggesting their use in engineering predictions.U.S. Department of the InteriorU.S. Geological SurveyOpe
