Comparative analysis of CFD models for jetting fluidized beds: The effect of inter-phase drag force

In the Eulerian–Eulerian approach for simulating gas–solid two-phase flow, a proper selection of an interfacial force to describe the momentum transfer between the two phases has a significant influence on the particle dynamics. Based on a detailed review of the inter-phase drag force models, a simple two-fluid model with zero particle-phase viscosity is used to investigate the effects of inter-phase drag force on the jet characteristics in a two-dimensional jetting fluidized bed. The simulation results from different inter-phase drag force models are compared with a designed experimental study. Both qualitative and quantitative results show that the jet behavior, including the distribution of solid volume fraction, bed pressure drop, jet penetration depth and jet frequency, could be significantly affected by the selection of drag force models. None of the models assessed in this work could predict all these parameters accurately. Some models can predict the averaged value well but are weak in predicting the dynamics and vice versa, which calls for a caution in interpreting data based on a single drag model.

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► The effect of drag forces on jetting dynamics in a fluidized bed is investigated.
► Six drag models are examined and compared with the experiments.
► None of the models could predict both averaged and dynamic values reliably.
► Some can predict the averaged values well but weak in dynamics, and vice versa.
► The Dallavala drag force model was recommended as a first estimation.