<![CDATA[Understanding the relationship between gas–solid hydrodynamics and localized bed-to-wall heat transfer is important for circulating fluidized beds (CFBs). This study investigates the effects of superficial gas velocity on particle redistribution and localized wall heat transfer in a three-dimensional full-loop CFB using computational fluid dynamics coupled with the discrete element method (CFD–DEM). Five velocities (1.5284–3.0105 m/s) were examined at a reported solids inventory of 224.975 kg/m³, with a heated wall at 373 K and initial gas and particle temperatures of 298 K. Predicted axial suspension-density and heat-transfer-coefficient trends were qualitatively compared with published experimental observations. The simulations reproduced characteristic core–annulus circulation and showed that increasing gas velocity promoted more uniform axial particle distributions. Local heat-transfer coefficients generally increased with velocity, but responses varied along the riser. Higher coefficients occurred in the lower region, whereas differences among velocity cases became more pronounced toward the upper heated region. Gas–wall convection and particle-mediated conduction exhibited different local responses. Among resolved particle–wall conductive pathways, non-contact conduction through the intervening gas dominated, while direct contact conduction contributed comparatively little. The study extends the characterization of the spatially dependent hydrodynamic–thermal relationship to a lower superficial gas-velocity range without proposing a new heat-transfer mechanism.]]>
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