Determination of Cluster Hydrodynamics in Bubbling Fluidized Beds by the EMMS Approach

Document Type : Original Paper

Authors

Oil and Gas Processing Centre of Excellence, School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran

Abstract

The local solid flow structure of gas-solid bubbling fluidized bed was investigated to identify and characterize the particle clusters. Extensive mathematical calculations were carried out using the energy-minimization multi-scale (EMMS) approach for evaluating cluster properties including the velocity, the size and the void fraction of clusters in the dense phase of the bed. The results showed that by increasing the gas velocity, the void fraction of clusters increases and also the larger portion of solids move in the bed in the form of cluster.  Modeled results were in good agreement with the experimental data reported in literature in terms of the velocity, the size the void fraction of clusters. The results of this study help to comprehend the hydrodynamics of clusters in gas-solid bubbling fluidized beds.

Keywords


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