Abstract
Turbulent fluidized bed possesses a distinct advantage over bubbling fluidized bed in high solids contact efficiency and thus exerts great potential in applications to many industrial processes.Simulation for fluidization of fluid catalytic cracking(FCC)particles and the catalytic reaction of ozone decomposition in turbulent fluidized bed is conducted using the Eulerian-Eulerian approach,where the recently developed two-equation turbulent(TET)model is introduced to describe the turbulent mass diffusion.The energy minimization multi-scale(EMMS)drag model and the kinetic theory of granular flow(KTGF)are adopted to describe gas-particles interaction and particle-particle interaction respectively.The TET model features the rigorous closure for the turbulent mass transfer equations and thus enables more reliable simulation.With this model,distributions of ozone concentration and gas-particles two-phase velocity as well as volume fraction are obtained and compared against experimental data.The average absolute relative de-viation for the simulated ozone concentration is 9.67％which confirms the validity of the proposed model.Moreover,it is found that the transition velocity from bubbling fluidization to turbulent fluidization for FCC particles is about 0.5 m·s-1 which is consistent with experimental observation.
维普
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