A novel phase inversion model was developed to describe the hydrodynamics in turbulent fluidized beds. The proposed model was coupled by a bubble-emulsion two phase model and a gas-cluster two phase model, which was derived from the typical mesoscale structures of two coexisting regions in turbulent fluidized beds. In the dense, bubbling region, the bubble-based interphase forces were used, while in the dilute, dispersed region, the cluster-based interphase forces were developed. The criterion of phase inversion, namely bubble-to-gas, emulsion-to-cluster, or vice versa, was also proposed and tested. Simulation results were compared with experimental data under different conditions to validate the model. The interphase forces acting on bubble or cluster were analyzed to study the radial nonuniformity of solid volume fraction. A coarse grid was utilized in this model, showing more capacity for the industrial scale-ups. (C) 2015 Elsevier B.V. All rights reserved.