Comparative analysis of CFD models for jetting fluidized beds: Effect of particle-phase viscosity

Under the Eulerian–Eulerian framework of simulating gas–solid two-phase flow, the accuracy of the hydrodynamic prediction is strongly affected by the selection of rheology of the particulate phase, for which a detailed assessment is still absent. Using a jetting fluidized bed as an example, this work investigates the influence of solid rheology on the hydrodynamic behavior by employing different particle-phase viscosity models. Both constant particle-phase viscosity model (CVM) with different viscosity values and a simple two-fluid model without particle-phase viscosity (NVM) are incorporated into the classical two-fluid model and compared with the experimental measurements. Qualitative and quantitative results show that the jet penetration depth, jet frequency and averaged bed pressure drop are not a strong function of the particle-phase viscosity. Compared to CVM, the NVM exhibits better predictions on the jet behaviors, which is more suitable for investigating the hydrodynamics of gas–solid fluidized bed with a central jet.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The effect of particulate rheology on jetting dynamics in a fluidized bed is investigated. ► Different viscosity model are examined and compared with the experiments. ► Constant viscosity model with particle viscosity of 0.10–1.00 Pa s is in agreement with the experiments. ► A simple two-fluid model with zero particle viscosity can predict jetting behaviors.