This study proposes a model to predict the temperature effect on the onset velocity of turbulent fluidization (u(c)) of Geldart type A particles. It was found that void splitting could occur in the whole bed when the initial bubble size at the distributor (d(bo)) was greater than the maximum stable bubble size (d(bmax)) or the equilibrium bubble size (d(beq)). The proposed model was successful to fit the trend of temperature effect on the uc. When the bubble growth was limited_x000D_ by the d(bmax), the u(c) increased with an increase of temperature. However, when the d(beq) was smaller than d(bmax), the u(c) decreased with an increase of temperature because the minimum fluidizing velocity and thus the d(beq) decreased. The u(c) increased initially and decreased later when the d(beq)/d(bmax) starting with the ratio >1 decreased to the ratio <1 as temperature increased. The present model predicted the trend properly that any other existing correlations could not be able to reflect.

Model Temperature Effect Transition Velocity Onset Velocity Turbulent Fluidized Bed

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