Particle velocity profiles in a circulating fluidized bed riser of square cross-section

Modeling of axial bed-to-wall heat transfer in a CFB combustor with abrupt riser exit geometry

“…Effect of exit structure on the axial bed density profile is reported by Brereton and Grace [5] with experimental verification for three different exit geometries. The maximum upward velocity was shifted to the exit side and the wall layer seemed to be thicker on the opposite side as reported by Zhou et al [6]. Grace [7] observed that the solid particles reach the top of the riser due to their inertia and thereby missing the exit; strikes the top wall and flows back down near the top zone wall of the riser.…”

Modelling of dense gas-particle flow in a circulating fluidized bed by Distinct Cluster Method (DCM)

“…The riser geometry has considerable influence on the hydrodynamics of CFBs [36,37,38]. Experimental results show that the voidage and velocity profiles in a CFB with square-crosssection are different from that with a circular cross-section [32,37,38]. The corners impact the two-phase flow field significantly.…”

“…The voidage and velocity profiles in a CFB with square-cross-section was experimentally studied by Zhou et al [37,38] using a fiber optic probe. The measurement results of the lateral profiles for mean vertical particle velocity and mean bed voidage are shown in Figs.…”

Numerical study of particle cluster flow in risers with cluster-based approach

“…Some researchers measured the descent velocities of clusters of particles near the wall in circulating fluidized beds. Among them are Rhodes et al (1992), Zhou et al (1995), Zhang et al (1995), and Noymer and Glicksman (2000). Most recently, Mostoufi and Chaouki (2004) validated the existence of clusters in circulating fluidized beds by analyzing tracers time-position data using radioactive particle tracking method.…”