CFD SIMULATION OF A BUBBLING FLUIDIZED BED USING LATTICE BOLTZMANN BASED DRAG MODELS
Carlos Manuel Romero Luna1; Ivonete Ávila1; Gretta Larisa Aurora Arce Ferrufino2
1 UNESP - Univ Estadual Paulista, Faculty of Engineering at Guaratinguetá, Department of Energy; 2 National Institute For Space Research, Combustion and Propulsion Associated Laboratory
doi:10.20906/CPS/COB-2015-2453
Resumo
A fluidized bed is an important operation unit for gas-solid contact. Some of the major applications include fluid catalytic cracking (FCC), combustion, gasification, pyrolysis, polymerization, among others. The performance of these applications mainly depends on a suitable understanding of gas-solid flow hydrodynamics, which influences the heat and mass transfer processes. In CFD simulations, the description of gas-solid flow hydrodynamics relies of a drag model to account the drag force. Because there are many applications of gas-solid flow in different conditions, different drag models have been reported in the literature. Though there have been published studies involving different drag models, there are few studies concerning drag models derived from Lattice Boltzmann simulations applied to a bubbling fluidized bed. This work provides a comprehensive study of drag models derived from Lattice Boltzmann simulations reported by Hill et al. (2001), van der Hoef et al.(2005), and Beetstra et al. (2007), in order to assess their performance in simulating gas-solid flow hydrodynamics in a bubbling fluidized bed. A CFD model using the MFIX code based on the Eulerian-Eulerian approach used along with KTGF was used to simulate a 2D bubbling fluidized bed with Geldart B particles. Finally, the simulation results are validated with the experimental data from Taghipour et al. (2005).
Palavras-chave: CFD; bubbling fluidized bed; Lattice Boltzmann drag models