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Glicksman’s viscous limit set of dimensionless parameters have been investigated using experimentally verified computational fluid dynamics model. Simulations have been performed for the two bubbling fluidized beds with different particle sizes and densities. Dimensionless average pressure drops across the bed height, dimensionless pressure standard deviations and dimensionless relative pressures have been investigated as a function of dimensionless superficial gas velocities for the two beds. Fluctuation of solid volume fraction and contours of solid volume fraction have also been investigated at different dimensionless gas velocities. Time series data of the pressure fluctuation and solid volume fraction are compared. The results indicate that the fluid dynamic similarity between two beds holds up to particle Reynolds number of 15. After this, the bubble activities in the two beds start to deviate significantly. The results of the work show that the analysis of solid volume fraction fluctuation gives higher accuracy than time-series pressure fluctuation when scaling the bubbling fluidized bed within the viscous limit.
fluidized bed, scaling, viscous limit, Glicksman, CFD
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