A new model for the prediction of the behaviour of fluidized beds

We derive a new model for the prediction of the transition between homogeneously expanded and bubbling fluidized beds. The model contains new terms in both the particle and fluid phase momentum balance equations and requires only the use of an experimental drag force correlation. Based on a simplified quasi-equilibrium formulation a minimum bubbling criterion is obtained and compared with a large number of experimental results. The model has been extended to two and three dimensions and CFD calculations are included to show the predictions for finite non-linear perturbations of fluidized beds of Geldart type A and B powders.