Review of Stability Criteria Based on Heuristic Approach

Review of Stability Criteria Based on Heuristic Approach 

Walhs (1969) proposed a very elegant and simple criterion for the transition in fluidized beds. The criterion is based on the concept of elasticity of fluidized beds. It assumes that a fluidized bed resists deformation hke any 

Slis et al. (1959) investigated the voidage propagation velocity. The authors not only provided the theoretical basis but provided an excellent experimental support for u. Therefore, this investigation has been used extensively by the subsequent workers in this area. Following is the mathematical derivation of in its simplest form. For more comprehensive derivation, the original work of Slis et aL (1959) is recommended. 

Considering the mass balance on the dispersed phase, if in time At the distance traveled by the sharp front is A/i, then 

In the limiting case of infinitesimally small change in the gas velocity, we get the following relation  

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IV. Review of Stability Criteria Based on Heuristic Approach... 

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