CFD simulations for prediction of scaling effects in pharmaceutical fluidized bed processors at three scales

Experimental operation of three fluidized bed processors is compared with CFD simulation results. The capacities of the fluidized bed processors represent two orders of magnitude scale-up. Qualitative fluidization patterns as well as quantitative data are compared with simulated processor operation. The numerical method and simulation approach were found to successfully predict the flow behavior of several different sizes of fluidized beds based solely on material properties, processor loading, inlet air flow rate and fluidized bed process geometry.

The spouting bed behavior observed in experiments was also seen in simulations. The graph shows that a central jet of particles being ejected into freeboard for both low and high flow cases. The particle volume fraction and mass flux indicate that the majority of particle and gas transport is occurring at the center of fluidized bed – consistent with spouting behavior.Figure optionsDownload as PowerPoint slideHighlights
► A 3D CFD model was developed to predict flow behaviors of fluidized beds.
► The spouting or bubbling flow behaviors were observed in simulation and experiment.
► CFD simulation may be of assistance in selecting operating parameters for scale up.