Settling velocity permeable

Clark, P.E. and Quadir, J.A. "Prop Transport in Hydraulic Fractures A Critical Review of Particle Settling Velocity Equations," SPE/DOE paper 9866, 1981 SPE/DOE Low Permeability Symposium, Denver, May 27-29. 

Clark, P.E. and Guler, N. "Prop Transport in Vertical Fractures Settling Velocity Correlations," 1983 SPE/DOE paper 11636, SPE/DOE Symposium on Low Permeability, Denver, March 14 16. 

Particle characterization, i.e. the description of the primary properties of particles in a particulate system, underlies all work in particle technology. Primary particle properties such as the particle size distribution, particle shape, density, surface properties and others, together with the primary properties of the liquid (viscosity and density) and also with the concentration and the state of dispersion, govern the other, secondary properties such as the settling velocities of the particles, the permeability of a bed or the specific resistance of a filter cake. Knowledge of these properties is vital in the design and operation of equipment for solid-liquid separation. 

Calculation of the terminal velocity of a porous sphere is useful and important in applications in water treatment where settling velocities of a floe or an aggregate are estimated. It is also important in estimation of terminal velocities of clusters in fluidized bed applications. The terminal velocity of a porous sphere can be quite different from that of an impermeable sphere. Theoretical studies of settling velocity of porous spheres were conducted by Sutherland and Tan (1970), Ooms et al. (1970), Neale et al. (1973), Epstein and Neale (1974), and Matsumoto and Suganuma (1977). The terminal velocity of porous spheres was also experimentally measured by Masliyah and Polikar (1980). In the limiting case of a very low Reynolds number, Neale et al. (1973) arrived at the following equation for the ratio of the resistance experienced by a porous (or permeable) sphere to an equivalent impermeable sphere. An equivalent impermeable sphere is defined to be a sphere having the same diameter and bulk density of the permeable sphere. 

K Matsumoto, A Suganuma. Settling velocity of a permeable model floe. Chem Eng Sei 32 445-447, 1977. 

Clark, P. E. and N. Giiler, Prop transport in vertical fractures settling velocity correlations, SPE/DOE Symposium on Low Permeability, Denver, Colorado, 1983, paper SPE/DOE 11636. 

Kirkby, L. L. and H. A. Rockefeller, Proppant settling velocities in nonflowing slurries, SPE/DOE Low Permeability Gas Reservoirs Symposium, Denver, Colorado, 1985, paper 13906. 

The fluid flow in a fluidized bed is related to a flow in a porous medium. The solid lattice constituted by the particles slows down the flow and produces a head loss. For the fluidized bed, the situation is more complex than for a settled bed. As the velocity of the fluid is increased, the thickness Hf of the bed grows and its porosity e increases. These two quantities are not geometrical data characterizing the bed they vary according to the fluid flow. The more the bed expands via the fluidization process, the greater its permeability becomes. Because of the increase in fluid velocity and the increase in the permeability k of the bed resulting from fluidization, the critical Reynolds nitmber Re = = 10 (which sets the... 

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