Numerical simulation and experimental analysis of gas/solid flow systems: 1999 Fluor-Daniel Plenary lecture

Gas/solid flow systems, including fluidized beds, are an essential part of many chemical processes. The optimum design and scale-up of these systems r equires a through understanding of gas/solid flow patterns. Achievement of this understanding involves the development of experimental flow measuremen t techniques, and experimentally verified multiphase flow equations and num erical simulation tools. This paper provides a brief review of current tech niques in solid flow measurement and recent contributions of the multiphase flow approach to gas/solid flow systems and fluidization. It features a re view of the Eulerian approach, as well as different governing and constitut ive equations, including the kinetic theory approach for cohesive and non-c ohesive particles. The effects of inlet, outlet and boundary conditions are also discussed. Two- and three-dimensional transient numerical simulations of gas/solid flow patterns in circulating and bubbling fluidized beds are presented, along with a comparison of the predicted flow parameters with la rge-scale experimental data. In addition, recent improvements in the comput ational code to simulate a real process with complex geometries, developed in partnership with Fluent and AEA Technology, are highlighted. The paper i s concluded with a discussion of the limitations and opportunities for rese arch and development in this area. (C) 2001 Elsevier Science B.V. All right s reserved.