Theoretical analysis of the flow regimes and their characteristics in vertically flowing gas-solids suspensions

This paper analyses the detailed flow structure characteristics of a vertical, fully developed gas-solids suspension. It is based on an asymptotic approach to general multiphase flow equations, in the range of low or moderate solids concentrations. Three distinct flow structures are identified, defining the Similar Profiles, Transition and Dense Phase Flow Regimes, as well as the local mechanism generating the transitions. The predicted properties of the trends of variation of local flow variables, with overall solids loading are, then, compared with existing experimental data. The observed wide agreement encourages the use of the theory for the interpretation and the prediction of the behavior of existing industrial units. (C) 2003 Elsevier B.V. All rights reserved.