Viscous non-Newtonian flow in packed beds: effects of column walls and particle size distribution

Abstract

New extensive pressure loss measurements are reported on the laminar flow of inelastic polymer solutions in packed beds made up of spheres of uniform size as well as mixtures of two different sizes. The importance of wall effects is demonstrated by using a range of column to particle diameter ratios (5.8 to 20). A methodology of modifying the existing frameworks to account for wall effects has been outlined. Similarly, an appropriate mean particle diameter has been identified which provides an adequate representation of the pressure loss data for mixed beds of two different size spheres. All in all, the results reported herein embrace the following ranges of physical and kinematic conditions: power law index, 1-0.72; voidage, 0.3-0.42; and Reynolds number, 1.8 × 10^-4-0.06.