Inertial flow structures in a simple‐packed bed of spheres

The detailed characteristics of the interstitial velocity distributions in pores are critical to understanding heat and mass transfer in a packed bed of granular material. The velocity distributions in a pore that models a simple-packed bed were measured directly by a magnetic resonance imaging technique. With an increase in the Reynolds number from 12.17 to 59.78-204.74, the increase and decrease in main flow velocity did not correspond to the local pore geometry, as is the case with a creeping flow. This indicated that inertial forces dominate over viscous forces. For example, at the Reynolds number of 204.74, the fluid penetrated through the center of the pores like a jet with negligible change of velocity. Circulation in the surrounding stagnant spaces generated eight symmetrical eddies in the plane perpendicular to the main flow direction.

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