Dense-phase fluidized beds solids mixing

Since the solid particles in the spouted bed are well mixed, their average temperature in different parts of the annulus can be considered to be the same, just as in the case of a fluidized bed. The maximum value of the heat transfer coefficient in the h-U plot is also similar to that in a dense-phase fluidized bed [Mathur and Epstein, 1974]. 

None of the models discussed above are versatile enou for scale-up purposes because of their incomplete treatment of the coupled complex phenomena occurring in the fluidized bed. The main difference in the various models is their treatment of the gas flow in the two phases and in the solids mixing mode in the dense phase. 

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